Prepared and filed by St Ives Financial

VIA EDGAR

Mr. Karl Hiller

United States Securities and Exchange Commission

Division of Corporation Finance

100 F Street, N.E.

Washington, D.C. 20549

Facsimile No.: (202) 772-9368

Re: Chemical and Mining Company of Chile Inc. Form 20-F for Fiscal Year Ended December 31, 2005 Filed on June 30, 2006 (File No. 001-12250)

Dear Mr. Hiller:

This letter is in response to the comment letter of the staff (the “Staff”) of the Securities and Exchange Commission (the “Commission”) dated December 4, 2006 (the “Comment Letter”) related to the annual report on Form 20-F for the fiscal year ended December 31, 2005 (the “Form 20-F”) of Chemical and Mining Company of Chile Inc. (the “Company”).

In connection with responding to the Comment Letter, the Company acknowledges that the Company is responsible for the adequacy and accuracy of the disclosure in the filing, that the Staff comments or changes to disclosures in response to Staff comments do not foreclose the Commission from taking any action with respect to the filing, and that the Company may not assert Staff comments as a defense in any proceeding initiated by the Commission or any person under the federal securities laws of the United States.

The Company’s responses to the Staff’s comments are set forth below. References to the “Company”, “we”, “us” and “our” in the responses set forth below are to the Company, unless the context otherwise requires. All references in the Company’s response to pages and captioned sections are to the Form 20-F as originally filed. Capitalized terms used in this letter and not otherwise defined herein have the meaning ascribed to them in the Form 20-F.

For convenience, the Company has included the SEC staff’s comments in italics followed by the Company’s response.

 


Form 20-F for the Year ended December 31, 2005

Comment 1:

Controls and Procedures, page 91

1.

Please revise the third paragraph of your disclosure to state whether there was any change in your internal control over financial reporting that occurred during the period covered by your annual report, instead of subsequent to such period, that has materially affected, or is reasonably likely to materially affect, your internal control over financial reporting, to comply with the guidance in Item 15(d) of Form 20-F.

Response 1:

We confirm that there were no changes in our internal control over financial reporting that occurred during the period covered by our annual report that have materially affected, or were reasonably likely to materially affect, our internal control over financial reporting. In future filings, the Company’s disclosure will be in accordance with the Commission’s comment.

Comment 2:

Principal Accountant Fees and Services, page 92

2.

Please describe the nature of the services comprising the fees included in the “Other Fees” category, which totaled $106.7 thousand for fiscal year 2005 as required by Item 16C(d) of Form 20-F.

Response 2:

For the year ended December 31, 2005 the services provided by the Company’s external auditors included in the “Other Fees” category, totalling $106.7 were at follows:

2


Other Fees by affiliate     2005     Corrected  
      US$     PCAOB
Fee
Category
 

 
SQM Chile              
1. Review of the Company’s accounting for the impact of the reorganization of PCS Yumbes (currently SQM Industrial S.A.) 1     12,275     1  
2. Review of the Company’s accounting for the impact of the reorganization of Isapre Norte Grande Ltda.     4,209     1  
3. Review of the procedures documented by the Company related to a foreign currency hedging relationship under both Chilean GAAP and US GAAP     14,029     1  
4. Review of the tax consequences of the acquisition of DSM initially determines by the Company.     6,839     3  
Total SQM Chile     37,352        
             
SQM Europe              
5. Review of the tax consequences of the acquisition of DSM and review of the tax implications of the lawsuit with Generale de Nutrition Vegetales SAS as initially determines by the Company. 2     50,000     3  
6. Review of the Company’s income tax return     17,696     3  
Total SQM Europe     67,696        
               
SQM North America              
7. Reimbursement of out of-pocket expenses     1,683     1  
Total SQM North America     1,683        
               
TOTAL     106,731        

1 As discussed in Note 28 to the Consolidated Financial Statements

2 As discussed in Note 27 to the Consolidated Financial Statements

The fees presented above were considered individually immaterial and were disclosed in the “Other Fees” category. In future filings we will present the following disclosure, including the amended classification of certain expenses for the year ended December 31, 2005:

   Year ended December 31,  
 
 
  2005     2004  
   
   
 
Audit fees   555.2     446.9  
             
Audit-related fees       11.8  
Tax fees   168.9     16.0  
Other fees        
Total fees   724.1     474.7  

Audit fees in the above table are the aggregate fees billed by Ernst & Young in connection with the audit of our annual Consolidated Financial Statements, as well as the review of other statutory filings.

Audit-related fees in the above table are fees billed by Ernst & Young for assurance and related services that are reasonably related to the performance of the audit or review of our financial statements and are not reported under "Audit Fees."

Tax fees in the above table are fees billed by Ernst & Young for tax advice and tax planning services.

Financial Statements

Comment 3:

Consolidated Statements of Cash Flows, page F-5

3.

Please detail for us the nature of items included in the operating activities line items “Other credits to income not representing cash flows” and “Other charges to income not representing cash flows.”

Response 3:

The Company sets forth in detail the nature of items included in the operating activities line items “Other credits to income not representing cash flows” and “Other charges to income not representing cash flows.”

3


 

 

 

2005

 

2004

 

2003

 

 

 


 


 


 

Other credits to income not representing cash flows

 

(10,109

)

(1,919

)

(2,793

)

Utilization of tax loss carry-forwards

 

0

 

0

 

(637

)

Deferred income taxes benefit for tax loss

 

(5,602

)

0

 

0

 

Adjustment of provision included in OIFE 1

 

(2,203

)

(389

)

(422

)

Minor adjustment of affiliates’ equity

 

(1,143

)

(413

)

(973

)

Discounts obtained from suppliers

 

(598

)

(482

)

(606

)

Other minor credits to income not representing cash flows

 

(562

)

(635

)

(155

)

 

 


 


 


 

 

 

(10,109

)

(1,919

)

(2,793

)

 

 


 


 


 

Other charges to income not representing cash flows

 

87,689

 

59,092

 

29,433

 

Provision for Corfo royalties

 

1,855

 

1,360

 

 

 

Deferred income taxes benefit for tax loss

 

0

 

12,635

 

13,864

 

Provision for legal expenses for GNV lawsuit and other legal expenses

 

5,000

 

873

 

1,100

 

Provision for marketing expenses

 

4,130

 

2,761

 

2,093

 

Provision for employee incentive plans

 

8,215

 

3,942

 

992

 

Adjustment of provision for severance indemnities

 

8,199

 

5,389

 

3,106

 

Provision for income taxes

 

38,427

 

13,938

 

2,829

 

Adjustment of provision for vacation

 

4,447

 

3,501

 

2,429

 

Refund of 10% of custom duties pursuant to Law 18,480

 

0

 

672

 

0

 

Non-capitalizable exploration project expenses and provisions for damages and liquidation of assets2

 

12,156

 

7,664

 

0

 

Other minor charges to income not representing cash flows

 

5,260

 

6,357

 

3,020

 

 

 


 


 


 

 

 

87,689

 

59,092

 

29,433

 

 

 


 


 


 

1

OIFE: other financial income

2 The exploration project expenses, consistent with the explanation in response 4, are capitalized under “Other long-term assets”. The length of time covered by any exploration project could take more than a year. Therefore, when the determination is made that a sector covered by a specific exploration project does not have economic reserves, the expenses that were capitalized are written-off and charged to income. That is why this item does not represent cash flow in the period that is written off.

Comment 4:

Note 2 Summary of Significant Accounting Policies, page F-13

o) Mining development cost, page F-13

4.

Please expand your disclosure to discuss the point at which you begin capitalizing and amortizing mining costs and the method you use to amortize such costs. Under U.S. GAAP, before mining costs are considered development related and capitalizable, you must establish proven and probable reserves as defined in Industry Guide 7. Capitalized mining costs are ordinarily amortized using the unit of production method using proven and probable reserves.

4


Include a reconciling item between Chilean and U.S. GAAP to the extent you capitalize your mining costs prior to establishment of proven and probable reserves, utilize other than the unit of production amortization method, and/or utilize other than proven and probable reserves in your amortization method application.

Response 4:

The Company expands below its disclosure of mining development cost in accordance with the Commission’s comment. In future filings our disclosure will be in accordance with the Commission’s comment.

The Company’s accounting for mining development costs is consistent with US GAAP. Mining costs are capitalized and amortized upon the establishment of proven and probable reserves based on definitions consistent with Industry Guide 7.

Mine exploration costs and stripping costs to maintain production of mineral resources extracted from operating mines are considered variable production costs and are included in the cost of inventory produced during the period. Mine development costs at new mines, and major development costs at operating mines outside existing areas under extraction that are expected to benefit future production are capitalized under “other long-term assets” and amortized using a units-of-production method over the associated proven and probable reserves. The Company determines its proven and probable reserves based on drilling, brine sampling and geo-statistic reservoir modeling in order to estimate mineral volumes and composition.

All other mine exploration costs, including expenses related to low grade mineral resources rendering the reserve not economically exploitable, are charged to the results of operations in the period in which they are incurred.

5


Comment 5:

Engineering Comments

Property, Plant and Equipment, page 33

Reserves, page 38

5.

We note your reserve estimates for your Caliche and Atacama Salar Brines mines. Please tell us in detail how you estimate your reserves for these two types of mineral deposits, and provide the detailed reserve estimates and supporting materials for one mine from your caliche deposits group and one mine from your brine mines as examples. In addition, provide justification for the basis you use to distinguish between proven and probable reserves for these two categories of mines.

Response 5:

Explanation of our Reserve Estimates for the Caliche Ore Mines

Proven and probable reserves of nitrates and iodine contained in the ore called “caliche” are calculated annually on the basis of information obtained from the various sectors of mining property that have been explored by means of regular drill hole grid patterns. The Reserves have been grouped geographically into 6 different sectors or mines:

I Region of Chile:

 

Nueva Victoria

 

Mapocho

 

Soronal

II Region of Chile:

 

Pedro de Valdivia

 

María Elena

 

Pampa Blanca.

6


Following is a description of the different stages in the evaluation process for nitrate and iodine proven and probable reserves.

A.

Methodology for Evaluating and Calculating Proven Reserves

1.

Updating of Geological and Topographical Planimetrics and of chemical analysis data (mineral grade and saline matrix)

The Geological Data Base for each area or mine is updated with newly available information concerning geological soundings, both on the surface and below ground, including data on lithology, geomechanics, compaction, and hardness of the mineral. This Geological Data Base is also being permanently updated with chemical analysis obtained in exploration activity carried out by means of drill core samples.

A Geological Model has been defined for each area or mine. These Geological Models are built up by interpreting vertical and horizontal sections containing the principal data obtained in drilling, which results in geological units in three dimensions (overburden, caliche layer, lixiviated layer, etc).

2.

Geological Data Base

Information available in the Geological Data Base includes the grades of Nitrate and Iodine mineral, sampled every 0.5 meters along the vertical drill holes, which go down to a depth of 8 meters, plus the geological, lithological, geomechanical, and hardness parameters for each drilling section.

Example of Geological Data Base:

a. Drill hole identification Data:

                       

HOLE_ID

 

East

 

North

 

Height a.s.l.

 

Length

 

Fine Height

 


 


 


 


 


 


 

12661C

 

433701.42

 

7448049.89

 

1447.49

 

7.00

 

1.10

 

12662C

 

433751.19

 

7448050.25

 

1448.77

 

5.00

 

1.00

 

12663C

 

433800.02

 

7448049.94

 

1449.61

 

6.50

 

0.50

 

b. Chemical Analysis Data:

HOLE_ID

 

SAMPLE

 

FROM

 

TO

 

NaNO3

 

I2

 

WEIGHT

 


 


 


 


 


 


 


 

12661C

 

156413C

 

0.00

 

0.50

 

3.00

 

320

 

12.00

 

12661C

 

156414C

 

0.50

 

1.00

 

6.20

 

360

 

15.00

 

12661C

 

156415C

 

1.00

 

1.50

 

6.10

 

360

 

15.00

 

12661C

 

156416C

 

1.50

 

2.00

 

5.80

 

540

 

14.00

 

12661C

 

156417C

 

2.00

 

2.50

 

6.70

 

400

 

15.00

 

12661C

 

156419C

 

2.50

 

3.00

 

5.10

 

340

 

15.00

 

12661C

 

156419C

 

3.00

 

3.50

 

4.40

 

250

 

16.00

 

12661C

 

156420C

 

3.50

 

4.00

 

4.10

 

180

 

16.00

 

12661C

 

156421C

 

4.00

 

4.50

 

3.10

 

190

 

16.00

 

12661C

 

156422C

 

4.50

 

5.00

 

6.20

 

150

 

16.00

 

12661C

 

156423C

 

5.00

 

5.50

 

8.00

 

160

 

16.00

 

12651C

 

156424C

 

5.50

 

6.00

 

6.70

 

650

 

17.00

 

12651C

 

156425C

 

6.00

 

6.50

 

2.70

 

300

 

16.00

 

12661C

 

156426C

 

6.50

 

7.00

 

2.30

 

210

 

16.00

 

7


c. Geomechanical and geological characteristics data from drill holes.

HOLE ID

 

From

 

To

 

Thickness

 

Geology Code

 

Comment

 


 


 


 


 


 


 

12661C

 

0.00

 

1.80

 

1.80

 

30

 

Rugose surface

 

12661C

 

1.80

 

7.00

 

5.20

 

9

 

Sunk-drill hole

 

12662C

 

0.00

 

0.50

 

0.50

 

10

 

Leached

 

12662C

 

0.50

 

2.20

 

1.70

 

30

 

Rugose surface

 

12662C

 

2.20

 

5.00

 

2.80

 

9

 

Sunk-drill hole

 

12663C

 

0.00

 

1.50

 

1.50

 

10

 

Leached

 

12663C

 

1.50

 

2.30

 

0.80

 

30

 

Rugose surface

 

12663C

 

2.30

 

6.50

 

4.20

 

40

 

Rugose-leached mixture

 

d. Drill hole lithology data (by means of geological coding).

HOLE ID

 

From

 

To

 

Lithology Code

 

Clastic Code

 

Clay Code

 

Colour Code

 


 


 


 


 


 


 


 

12661C

 

0.00

 

0.50

 

2

 

5

 

1

 

1

 

12661C

 

0.50

 

1.00

 

2

 

5

 

1

 

1

 

12661C

 

1.00

 

1.50

 

2

 

5

 

1

 

1

 

12661C

 

1.50

 

2.00

 

2

 

5

 

1

 

1

 

12661C

 

2.00

 

2.50

 

2

 

5

 

1

 

1

 

12661C

 

2.50

 

3.00

 

2

 

5

 

1

 

1

 

12661C

 

3.00

 

3.50

 

2

 

5

 

1

 

1

 

12661C

 

3.50

 

4.00

 

2

 

5

 

1

 

2

 

12661C

 

4.00

 

4.50

 

2

 

5

 

1

 

2

 

12661C

 

4.50

 

5.00

 

2

 

5

 

1

 

2

 

12661C

 

5.00

 

5.50

 

2

 

5

 

1

 

2

 

12661C

 

5.50

 

6.00

 

2

 

5

 

1

 

2

 

12661C

 

6.00

 

6.50

 

2

 

5

 

2

 

2

 

12661C

 

6.50

 

7.00

 

2

 

5

 

2

 

2

 

e. Caliche chemical composition data (Saline matrix)

HOLE_ID

 

Project Code

 

LOCATIONX

 

LOVATIONY

 

LOCATIONZ

 

Na2SO4

 

Ca

 

Mg

 

K

 

SO4_Ap

 

KCIO4

 

NaCI

 

H3BO3

 

Na

 

K/Mg

 

Solubility

 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 

2000C

 

PB

 

434649.6

 

7446249.9

 

1439.4

 

32.20

 

5.85

 

1.39

 

0.63

 

11.47

 

0.05

 

14.50

 

0.49

 

8.89

 

0.45

 

269.4

 

2145C

 

PB

 

434649.9

 

7446450.0

 

1441.0

 

26.50

 

3.34

 

1.23

 

0.85

 

14.66

 

0.05

 

13.00

 

0.36

 

10.33

 

0.69

 

141.5

 

2080C

 

PB

 

434650.0

 

7446349.8

 

1440.8

 

35.90

 

6.74

 

1.35

 

0.94

 

15.56

 

0.05

 

8.90

 

0.30

 

8.59

 

0.70

 

205.8

 

2044C

 

PB

 

434650.5

 

7446299.8

 

1440.0

 

31.30

 

6.06

 

0.95

 

0.80

 

9.82

 

0.06

 

6.40

 

0.46

 

6.13

 

0.84

 

244.8

 

8


3.

Calculation of Reserves by means of Geostatistical methods

3.1.

Revision and exploration analysis of the Geological Data Bases.

1.

For any specific area in which reserves are to be evaluated, the following maps are available, among other maps: general location map (Fig. 1) and available resources distribution map (Fig. 2).



The evaluation of reserves takes into account both the distribution and thickness of the mineral-bearing caliche layer.

For each evaluation of reserves in a given sector or area, an analysis is carried out of the basic statistical information in the Geological Data Base, including the data histograms for each element to be evaluated.

9


Basic statistics information

 

VARIABLE

 

DATA

 

MIN

 

MAX

 

MEAN

 

ST_DESV

 

VARIANCE

 

COEF. OF VARIATION

 

KURTOSIS


 
 
 
 
 
 
 
 

NITRATE

 

67.153

 

0.1

 

21.2

 

5.28

 

3.79

 

14.33

 

0.72

 

4.5

IODINE

 

67.153

 

3

 

2272

 

376.28

 

320.31

 

102.599.6

 

0.85

 

9.15


In general, the histograms show asymmetrical distributions.

3.2.

Experimental Variography of Data

The experimental variography is built up from mineral grade data obtained in drilling; it is modeled and then adjusted according to the spatial correlation of the samples. This provides parameters such as ranges, sill, nugget effect and anisotropy, which are then used in the Kriging method.


10


 

3.3.

Kriging method for estimating ore grades

The evaluation of Reserves in each mine sector or area is done by means of a block model, in which each block represents the characteristics of the ore within it. To estimate the characteristics of each block, we use the information contained in the Geological Data Base as well as the geostatistical tools described below.

 

a)

Search parameters: To determine the optimum search radius, we take into account the spatial correlation of the samples that went into adjusting the variographic model, that is, the “range” in geostatistical methods.


11


 

b)

Block model: The Kriging method is used to determine the block model, which will serve to calculate ore grade by interpolation and assign it to the center of gravity of each block. The dimensions of each block are 25m x 25m x 0.5m. At this stage, the ISATIS software application is used.

 


 

c)

On the basis of the variographic model and the search parameters, data for each block is interpolated and entered. Next, a statistical analysis of information contained in the block model is carried out:

Basic statistics of the block model

 

VARIABLE

 

DATA

 

MIN

 

MAX

 

MEAN

 

ST_DESV

 

VARIANCE

 

COEF. OF VARIATION

 

KURTOSIS


 
 
 
 
 
 
 
 

NITRATE

 

625.001

 

0.55

 

20

 

4.8

 

1.99

 

3.96

 

0.42

 

4.89

IODINE

 

625.001

 

15

 

2000

 

327.2

 

163.72

 

26.805

 

0.50

 

8.04

 

d)

The block model (which includes estimated ore grades) is intersected with the Geological Model. Next, operational and mining program parameters are applied in order to determine which ore bodies are economically exploitable.

The above serves to draw up tonnage / ore-grade curves as a function of various cut-offs for each mineral being considered. Finally, a GIS-type software application (ArcView and MAPINFO) is used to make graphic representations of the Resources and Reserves plans.

 


12


 

Interaction of Block Model and Geological Model

 

Use of software for mining design and
planning

 

GIS software to graphically represent Resources and Reserves

The above process generates data bases for the 3D block model, containing all the necessary information for evaluating the proven reserves. The following is an example of 3D data bases.

3D Data Bases with various Geological Units

 

ID

 

1

 

J

 

K

 

X

 

Y

 

Z

 

UG

 

COTA_SUP

 

Nano3

 

12

 

Aire

 

SC

 

Manto

 

SUBY


 


 


 


 


 


 


 


 


 


 


 


 


 


 


167-40

 

167

 

40

 

66

 

433612.5

 

7443937.5

 

1422.25

 

1

 

1422.33

 

3.7

 

260

 

33.51

 

66.49

 

0.00

 

0.00

167-40

 

167

 

40

 

67

 

433612.5

 

7443937.5

 

1421.75

 

1

 

 

 

3.7

 

290

 

0.00

 

100.00

 

0.00

 

0.00

167-40

 

167

 

40

 

68

 

433612.5

 

7443937.5

 

1421.25

 

1

 

 

 

3.7

 

344

 

0.00

 

100.00

 

0.00

 

0.00

167-40

 

167

 

40

 

69

 

433612.5

 

7443937.5

 

1420.75

 

1

 

 

 

3.6

 

461

 

0.00

 

52.29

 

47.71

 

0.00

167-40

 

167

 

40

 

70

 

433612.5

 

7443937.5

 

1420.25

 

7

 

 

 

4.8

 

520

 

0.00

 

0.00

 

100.00

 

0.00

167-40

 

167

 

40

 

71

 

433612.5

 

7443937.5

 

1419.75

 

7

 

 

 

4.0

 

457

 

0.00

 

0.00

 

100.00

 

0.00

167-40

 

167

 

40

 

72

 

433612.5

 

7443937.5

 

1419.25

 

7

 

 

 

4.3

 

416

 

0.00

 

0.00

 

100.00

 

0.00

167-40

 

167

 

40

 

73

 

433612.5

 

7443937.5

 

1418.75

 

4

 

 

 

3.7

 

323

 

0.00

 

0.00

 

94.60

 

5.40

167-40

 

167

 

40

 

74

 

433612.5

 

7443937.5

 

1418.25

 

10

 

 

 

3.3

 

270

 

0.00

 

0.00

 

34.19

 

65.80

167-40

 

167

 

40

 

75

 

433612.5

 

7443937.5

 

1417.75

 

10

 

 

 

2.2

 

233

 

0.00

 

0.00

 

0.00

 

100.00

167-40

 

167

 

40

 

76

 

433612.5

 

7443937.5

 

1417.25

 

10

 

 

 

2.0

 

203

 

0.00

 

0.00

 

0.00

 

100.00

167-40

 

167

 

40

 

77

 

433612.5

 

7443937.5

 

1416.75

 

10

 

 

 

2.1

 

190

 

0.00

 

0.00

 

0.00

 

100.00

167-40

 

167

 

40

 

78

 

433612.5

 

7443937.5

 

1416.25

 

10

 

 

 

2.3

 

183

 

0.00

 

0.00

 

0.00

 

86.50

 

I, J, K

 

: Local coordinates for block model

X;Y;Z

 

: UTM coordinates

UG

 

: Geological unit code

COTA_SUP.

 

: Highest unit block altitude above sea level

Aire

 

: Percentage of block unit without caliche ore or waste into the block

SC

 

: Percentage of overburden into the block unit

Manto

 

: Percentage of caliche ore into the block unit

SUBY

 

: Percentage of waste into the block unit without Nitrate and Iodine

3.4.

Final calculation of Proven Reserves

For a given operational cut off, a calculation is made of the tonnage and grades of the proven reserves contained in the ore bodies represented by the 3D block model. The resulting ore grade is adjusted by operational factors which reflect the dilution of ore grade between the in-situ reserves and the reserves after extraction for processing. These factors are variable and they depend on the continuity of mineralization, the lithology, lixiviation of the ore body, geological sector, etc.

The tonnage of Reserves calculated in those sectors that have been explored with a 100 x 100 m drill hole grid pattern are corrected by a geological continuity factor in order to express it in terms of a 50 x 50 m pattern. This factor has been determined from practical experience at the various caliche mining operations.

13


 

B.

Methodology for Evaluating and Calculating Probable Reserves

The methodology for determining probable reserves, corresponding to data obtained from drill hole grid patterns having 200 m x 200 m spacing, is similar to that used for the proven reserves, in terms of interpretation, creation of the Geological Data Base and the application of limiting operational parameters, which help select the blocks that make up the reserve. Probable reserves, however, are obtained using a 2D block model, which takes into account the thickness of overburden, thickness of the caliche ore layer, mineral grade and density. The tonnage of each block is then calculated by means of the Polygon Method.

As in the case of proven reserves, the ore grade calculated for each sector is corrected by operational factors which reflect dilution of ore grades.

Explanation of our Reserve Estimates for the Atacama Salar Brines Mines

To determine the annual tonnage of ion reserves contained in the brine deposits recognized to date in the Salar de Atacama mining properties, the following stages are developed:

1.

Updating of Geological and Geochemical Planimetry

This includes incorporating new exploration information from either surface or stratigraphic sections, into the geological study defined in the year 2000.

This geological study divides the recognized deposit into 5 Deposits in accordance with its geochemistry and geological reconnaissance:

 

MOP 1 PRINCIPAL DEPOSIT (In operation)

 

MOP 2 SOUTH-WEST DEPOSIT

 

MOP 3 NORTH-WEST DEPOSIT

 

INTERMEDIATE DEPOSIT

 

SOP DEPOSIT (In operation)

All the above updated information is incorporated into the digital geological database and managed by a GIS software (“MAPINFO”).

2.

Brine Sampling

In each one of these 5 Deposits, brine samples are taken from production and exploration drill-holes. This sampling is realized in the month of January of each year. The breakdown of the sampled drill-holes in each Deposit is as follows:

 

MOP 1 PRINCIPAL DEPOSIT (In operation):. Samples are taken from production and exploration drill-holes, including a total of 233 drill-holes in a regular grid pattern spacing equal to 500 x 500 meters and a depth of 50 to 100 meters.

14


 

 

MOP 2 SOUTHWEST DEPOSIT: Samples are taken from exploration drill-holes, including 64 drill-holes in a regular grid pattern spacing equal to 1000 x 1000 meters and a depth of up to 100 meters.

 

MOP 3 NORTHWEST DEPOSIT: Samples are taken from exploration drill-holes, including 45 irregularly distributed perforations with a depth of up to 100 meters.

 

INTERMEDIATE DEPOSIT: Samples are taken from exploration drill-holes, including 25 drill-holes with 100 meters of depth.

 

SOP DEPOSIT: Samples are taken from exploration drill-holes, including 112 drill-holes with irregular distribution and a depth of 40 to 60 meters.

3.

Chemical Analysis

All the samples collected are analyzed in SQM Salar S.A.’s own laboratory for the purpose of determining the density of the brine and the value of the following chemical elements:

K%, Mg%, Li%, SO4%, H3BO3%, Na%, Cl%, Ca%, Density

The measuring method applied is ICP (Induction Coupled Plasma) and atomic absorption.

The results of these analyses are geo-referenced and stored in an Excel database.

4.

Reserves Evaluation

To estimate the proven and probable reserves existing by the end of 2005, the information and sampling realized in January 2006 are taken into consideration.

The method used in the evaluation of reserves corresponds to a geostatistical study using the ordinary Kriging method in 2D1, including the following stages:

4.1.

Updating of Variograms: Activity realized by external consultant.

4.2.

Entry of chemical data to the Kriging Program to obtain an estimated grade or concentration of the elements to be evaluated (K, SO4, Mg, Li, B, Ca, and H2O).

4.3.

The minimum evaluation unit used is a block measuring 500 x 500 meters of surface area and 30 meters of depth for the MOP 1 Principal, MOP 3 Northwest, Intermediate, and SOP Deposits. For the MOP 2 Southwest deposit, a block is configured of 500 x 500 meters of surface area and 50 meters of depth.

4.4.

A value is assigned to each block in a percentage of the Specific Yield which corresponds to the quantity of brine effectively drainable or exploitable in situ in each one of the evaluation units. This coefficient has been modeled and calibrated based on the MOD/FLOW and MT3D model (External Consultants: Pontificia Universidad Católica de Chile, DICTUC).

 


1

The program was designed for Salar de Atacama brines by external consultant expert in Geostatistics.

15


 

The value assigned to the MOP 1 Principal, Intermediate, and MOP 3 Northwest Deposits varies between 3% and 20% while the MOP 2 Southwest Deposit is 7% and SOP Deposit varies between 1 to 20%.

4.5.

Calculation of Reserves

To calculate the recoverable reserves of each Deposit, the chemical restrictions must be considered that will define the type of process that should be applied to the brines obtained. For this reason, each one of the blocks receives a characterization of the estimated SO4/Mg and SO4/(Mg+Li) ratio.

4.5.1.

Chemical Parameters considered

 

MOP 1, 2, and 3 Deposits

 

 

Ratio 

 

SO4/Mg = < 0.5

 

 

SO4/Mg > 0.5 and =< 1.1

 

 

SO4/Mg > 1.1 and =< 2.0

Elements to evaluate

 

K, Li, SO4, and B.

 

 

 

MOP 1 Deposit

 

 

Ratio 

 

SO4/(Mg+1.75Li) > 2.0

Elements to evaluate

 

K, Li, SO4, and B.

 

 

 

Intermediate Deposit

 

 

Ratio

 

SO4/Mg => 1.1 and =< 2.0

Elements to evaluate

 

K, Li, SO4, and B.

 

 

 

SOP Deposit

 

 

Ratio 

 

SO4/(Mg+1.75Li)=>1.8

 

 

Mg/Li > 6.3

 

 

SO4/K > 1.2

Elements to evaluate 

 

K, Li, SO4, and B.

 

 

 

Ratio 

 

SO4/Mg > 2.9, without complying with previous ratios.

Elements to evaluate

 

K, Li, SO4, and B.

4.5.2.

Calculation Method

Based on the chemical characteristics of each block, the volume of brine contained and the Specific Yield (drainable percentage), it is possible to calculate the quantity of K, Li, SO4 and B ions that can be extracted from each one of the different Deposits and for each one of the ranges of the SO4/Mg and/or SO4/(Mg+1.75Li) ratios.

MAPINFO software is used to sum up the corresponding blocks in accordance with the chemical selection parameters, which select the blocks that comply with the conditions established by the selection, providing accumulated tonnages for the various elements to be evaluated. With this same software, the distribution of the reserves evaluated in each one of the Deposits can be visualized planimetrically.

16


Example of Reserve Estimates and Supporting Materials for Area VIII of Sector 4 of Pampa Blanca Mine from our Caliche Deposits Group

a)

Below are the results of the tonnage / ore-grade curve for iodine, after applying the calculation methodology for proven and probable reserves to area VIII of sector 4 of Pampa Blanca mine.

Evaluation by Iodine (l2)

 

Cut off ppm

 

Average Grade

 

Tonnage (kMT)

 

Thickness (m)

 

 


 


 


 

 

I2(ppm)

 

NaN03(%)

 

ore (caliche)

 

overburden

 

ore (caliche)

 

overburden

 


 


 


 


 


 


 


 

350

 

473

 

4.9

 

867,029

 

383,369

 

1.9

 

1.1

 

400

 

502

 

5.1

 

640,591

 

285,977

 

1.8

 

1.1

 

450

 

546

 

5.4

 

417,318

 

172,941

 

1.8

 

1.0

 

b)

Example of spreadsheet with detail of Resources and Reserves in Sector 4 of the Pampa Blanca mine, by sector and with a cut-off of 350 ppm Iodine:

PAMPA BLANCA SECTOR 4 IODINE

 

 

 

Grid

 

Comment

 

kMt

 

%NaNo3

 

ppm I2

 

Thick. overb. m

 

Thick. ore. m

 

 

 


 


 


 


 


 


 


 

PAMPA BLANCA

 

50

 

SECTOR II

 

2,326,379

 

6.5

 

469

 

1.1

 

2.3

 

 

50

 

SECTOR VIII

 

867,029

 

4.9

 

473

 

1.1

 

1.9

 

 

50

 

SECTOR IX-X

 

1,681,142

 

5.9

 

472

 

1.0

 

1.8

 

 

50

 

SECTOR XI

 

1,016,496

 

5.3

 

469

 

1.8

 

2.8

 

 

50

 

SECTOR I

 

3,904,060

 

6.0

 

523

 

1.4

 

2.7

 

 

50

 

SECTOR III

 

1,013,235

 

5.5

 

440

 

1.2

 

1.8

 

 

50

 

SECTOR IV

 

899,531

 

6.8

 

487

 

0.8

 

2.5

 

 

50

 

SECTOR V

 

2,984,979

 

6.2

 

488

 

1.6

 

2.6

 

 

50

 

SECTOR VI

 

8,090,285

 

6.2

 

544

 

1.0

 

2.7

 

 

50

 

SECTOR VII

 

4,302,622

 

7.0

 

538

 

1.6

 

2.5

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Total grid 50  

 

27,085,759

 

6.2

 

512

 

1.3

 

2.5

(a)

                               

 

100

 

SECTOR 4

 

6,097,000

 

6.8

 

550

 

0.7

 

2.9

(b)

 

200

 

SECTOR 4

 

10,096,800

 

7.8

 

618

 

1.1

 

3.9

(c)

 

400

 

SECTOR 4

 

11,289,600

 

8.9

 

573

 

1.4

 

2.4

(d)

(a)

Total Resources in a 50 x 50 grid;

(b)

Total Resources in a 100 x 100 grid

(c)

Resources in a 200x200 grid

(d)

Resources in a 400x400 grid

17


 

c)

Example of spreadsheet summarizing proven reserves in Pampa Blanca mine, after applying the adjustment factor for dilution of estimated ore grades. Also shown is the adjustment applied to the 100 x 100 m drilling grid.

 

   

GEOLOGICAL RESOURCES DIC/31/2005

 

PROVEN RESERVES DIC/31/2005

 
   
 
 

Sierra Gorda

 

kMT

 

%NaNo3

 

ppm I2

 

kMT

 

%NaNo3

 

ppm I2

 

kMT

 

%NaNo3

 

ppm I2

 

kMT

 

%NaNo3

 

ppm I2

 

kMT

 

%NaNo3

 

ppm I2

 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 

Pampa Blanca-4(Cp)

 

27.1

 

6.2

 

512

 

6.1

 

6.8

 

550

 

27.1

 

5.3

 

461

 

4.3

 

5.8

 

495

 

31.4

 

5.4

 

466

(a)(b)

Pampa Blanca-4(Cp)

 

20.9

 

8.7

 

689

 

17.8

 

9.3

 

667

 

20.9

 

7.4

 

620

 

12.4

 

7.9

 

600

 

33.3

 

7.6

 

613

 

Ampliación Pampa Blanca

 

16.8

 

6.3

 

626

 

 

 

 

 

 

 

16.8

 

5.3

 

563

 

 

 

 

 

 

 

16.8

 

5.3

 

563

 

 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 

Total

 

64.7

 

7.0

 

599

 

23.9

 

8.7

 

637

 

64.7

 

6.0

 

539

 

16.7

 

7.4

 

573

 

81.4

 

6.3

 

546

(T1)

 


 


 


 


 


 


 


 


 


 


 


 


 


 


 


 

(T1)

Total Proven Reserves

d)

Example of spreadsheet summarizing Probable Reserves in Pampa Blanca mine, after applying the adjustment factor for dilution of estimated ore grades.

 

 

 

GEOLOGICAL RESOURCES DIC/31/2005

 

PROBABALE RESERVES 31/DIC/2005

 

 

 


 


 

 

 

GRID 200

 

GRID 200 PROY.

 

TOTAL PROBABLE

 

 

 


 


 


 

Sierra Gorda

 

kMT

 

%NaNo3

 

ppm I2

 

kMT

 

%NaNo3

 

ppm I2

 

kMT

 

%NaNo3

 

ppm I2

 


 


 


 


 


 


 


 


 


 


 

Pampa Blanca-3 (Cp)

 

27.6

 

9.8

 

580

 

27.6

 

8.3

 

522

 

27.6

 

8.3

 

522

 

Pampa Blanca-4 (Cp)

 

10.1

 

7.8

 

618

 

10.1

 

6.6

 

556

 

10.1

 

6.6

 

556

(c)

Pampa Blanca-5 (Cp)

 

51.9

 

9.2

 

588

 

51.9

 

7.8

 

529

 

51.9

 

7.8

 

529

 

Blanco Encalada (Cp)

 

48.3

 

10.5

 

425

 

48.3

 

8.9

 

383

 

48.3

 

8.9

 

383

 

Ampliación Pampa Blanca (Cp)

 

285.2

 

5.8

 

611

 

285.2

 

4.9

 

550

 

285.2

 

4.9

 

550

 

 


 


 


 


 


 


 


 


 


 

Total

 

423.1

 

7.1

 

585

 

423.1

 

6.0

 

526

 

423.1

 

6.0

 

526

(T2)

 


 


 


 


 


 


 


 


 


 

(T2)

Total Probable Reserves

e)

Summary Table of Proven and Probable Reserves, which includes Pampa Blanca Reserves

 

Mine

 

Proven Reserves
(millions of metric tons)

 

Nitrate Average Grade
(percentage by weight)

 

Iodine Average Grade
(parts per million)

 


 


 


 


 

Pedro de Valdivia

 

144.0

 

7.2

%

387

 

Maria Elena

 

146.8

 

7.3

%

415

 

Pampa Blanca

 

81.4

 

6.3

%

546

(T1)

Nueva Victoria

 

95.3

 

4.2

%

467

 

Mapocho

 

4.6

 

5.3

%

436

 

Soronal

 

158.9

 

7.1

%

405

 

 

Mine

 

Probable Reserves
(millions of metric tons)

 

Nitrate Average Grade
(percentage by weight)

 

Iodine Average Grade
(parts per million)

 


 


 


 


 

Pedro de Valdivia

 

134.7

 

6.9

%

441

 

Maria Elena

 

97.6

 

7.3

%

380

 

Pampa Blanca

 

423.1

 

6.0

%

526

(T2)

Nueva Victoria

 

66.0

 

3.7

%

443

 

Soronal

 

29.1

 

7.6

%

362

 

18


 

Example of Reserve Estimates and Supporting Materials for Atacama Salar Brines Mines

5.1.

Reception of chemical analysis and creation of database.

Analytical results are received from 479 sampled drill-holes. These results are electronically filed in an evaluation worksheet, as shown in Figure A.

Figure A

 

Sample

 

East

 

North

 

%K

 

%Mg

 

%Li

 

% S04

 

% H3B03

 

%Ca

 

H2O

 


 


 


 


 


 


 


 


 


 


 

W-1  

 

562585

 

7394136

 

3,87

 

1,42

 

0,23

 

0,71

 

0,32

 

0,06

 

70,3

 

W-10

 

563588

 

7394635

 

2,69

 

1,33

 

0,22

 

1,42

 

0,36

 

0,04

 

70,9

 

W-17

 

564094

 

7394635

 

3,45

 

1,62

 

0,28

 

0,93

 

0,42

 

0,05

 

70,6

 

W-2  

 

561990

 

7393637

 

3,08

 

1,86

 

0,33

 

1,10

 

0,44

 

0,04

 

71,1

 

W-18

 

564089

 

7395282

 

2,98

 

1,44

 

0,24

 

1,31

 

0,39

 

0,04

 

70,7

 

W-5  

 

563087

 

7394134

 

3,88

 

1,50

 

0,25

 

0,87

 

0,33

 

0,05

 

70,1

 

W-40

 

560992

 

7394146

 

2,65

 

1,65

 

0,28

 

1,54

 

0,37

 

0,03

 

70,9

 

W-35

 

561487

 

7393139

 

3,81

 

1,83

 

0,33

 

0,73

 

0,38

 

0,06

 

70,1

 

W-34

 

561993

 

7394158

 

2,57

 

1,42

 

0,24

 

1,56

 

0,37

 

0,03

 

70,9

 

W-38

 

560988

 

7393140

 

3,36

 

1,12

 

0,18

 

1,02

 

0,30

 

0,05

 

70,6

 

W-6  

 

563093

 

7394560

 

3,03

 

1,40

 

0,23

 

1,28

 

0,36

 

0,04

 

70,8

 

W-16

 

564122

 

7394169

 

2,55

 

1,21

 

0,19

 

1,59

 

0,38

 

0,04

 

70,7

 

W-54

 

561487

 

7392640

 

3,50

 

1,79

 

0,33

 

0,78

 

0,39

 

0,06

 

70,6

 

19


 

5.2.

Updating of variograms and evaluation software.

The grade information organized in a database is sent to an outside consultant, who, based on this information, builds the new variograms that indicate the geostatistical behavior of the ions to be evaluated and that allow defining the new scope of grade estimation used by the Kriging method, as shown in Figure B.

Figure B

 


20


5.3.

Assignation of attributes per block.

Numerical information is entered into evaluation software and graphs are produced demonstrating the generation of evaluated blocks. The chemical ratios (restrictions), Specific Yield, density and tonnage calculations are added to the previously generated blocks with grades. All this information can be displayed by means of a GIS or electronic worksheet as shown in Figure C.

FIGURE C

 


21


 

5.4.

Chemical selection parameters for the evaluation.

Once the prior process of assigning attributes to each one of the blocks is completed, the blocks are selected for determining the volume with the MAPINFO software and according to the chemical parameters and limits defined in section 4.5.1., which are based on economical criteria for obtaining different commercial products resulting from each ion.

This allows selecting and adding up the reserve blocks in accordance with their selection criteria, the results of which are shown in section 5.5.

5.5.

Reserve calculation and evaluation results

 

 

 

Chemical Parameter SO4/Mg <=0.5, January 2006

 

 

 

 

 

 

 

 

 


 

 

 

 

 

 

 

 

 

MOP 1 Deposit

 

MOP 2 S-W Deposit

 

MOP 3 N-W Deposit

 

 

 

Reserve

 

 

 


 


 


 

 

 


 

 

 

Proven

 

Probable

 

Err > 35%

 

Total

 

Proven

 

Probable

 

Err > 35%

 

Total

 

Proven

 

Probable

 

Err > 35%

 

Total

 

 

 

Proven

 

Probable

 

 

 


 


 


 


 


 


 


 


 


 


 


 


 

 

 


 


 

K

 

1.697

 

0.00

 

0.00

 

1.697

 

5.230

 

0.155

 

0.000

 

5.385

 

0.398

 

0.476

 

0.097

 

0.972

 

K

 

7.325

 

0.631

 

S04

 

0.177

 

0.110

 

0.026

 

0.314

 

0.074

 

0.444

 

0.037

 

0.555

 

0.000

 

0.100

 

0.146

 

0.247

 

SO4

 

0.251

 

0.654

 

Li

 

0.133

 

0.048

 

0.000

 

0.181

 

0.340

 

0.042

 

0.000

 

0.382

 

0.000

 

0.042

 

0.057

 

0.098

 

Li

 

0.473

 

0.132

 

H3BO3

 

0.192

 

0.00

 

0.00

 

0.192

 

0.206

 

0.296

 

0.000

 

0.502

 

0.044

 

0.075

 

0.000

 

0.119

 

B

 

0.077

 

0.065

 

 

 

 

Chemical Parameter SO4/Mg > 0.5- SO4/Mg <= 1.1, January 2006

 

 

 

 

 

 

 


 

 

 

 

 

 

 

MOP 1 Deposit

 

MOP 2 S-W Deposit

 

MOP 3 N-W Deposit

 

 

 

Reserve

 

 

 


 


 


 

 

 


 

 

 

Proven

 

Probable

 

Err > 35%

 

Total

 

Proven

 

Probable

 

Err > 35%

 

Total

 

Proven

 

Probable

 

Err > 35%

 

Total

 

 

 

Proven

 

Probable

 

 

 


 


 


 


 


 


 


 


 


 


 


 


 

 

 


 


 

K

 

3.179

 

0.000

 

0.000

 

3.179

 

0.502

 

0.236

 

0.000

 

0.738

 

2.492

 

0.889

 

0.097

 

3.479

 

K

 

6.174

 

1.125

 

S04

 

1.301

 

0.046

 

0.000

 

1.346

 

0.188

 

0.034

 

0.000

 

0.193

 

0.696

 

0.676

 

0.094

 

1.466

 

SO4

 

2.155

 

0.756

 

Li

 

0.260

 

0.030

 

0.002

 

0.292

 

0.005

 

0.045

 

0.000

 

0.050

 

0.111

 

0.092

 

0.120

 

0.324

 

Li

 

0.376

 

0.187

 

H3BO3

 

0.403

 

0.000

 

0.000

 

0.403

 

0.009

 

0.070

 

0.000

 

0.079

 

0.317

 

0.143

 

0.000

 

0.459

 

B

 

0.127

 

0.037

 

 

 

 

Chemical Parameter SQ4/Mg >1.1 SO4/Mg <= 2, January 2006

 

 

 

 

 

 

 


 

 

 

 

 

 

 

MOP 1 Deposit

 

MOP 2 S-W Deposit

 

MOP 3 N-W Deposit

 

 

 

Reserve

 

 

 


 


 


 

 

 


 

 

 

Proven

 

Probable

 

Err > 35%

 

Total

 

Proven

 

Probable

 

Err > 35%

 

Total

 

Proven

 

Probable

 

Err > 35%

 

Total

 

 

 

Proven

 

Probable

 

 

 


 


 


 


 


 


 


 


 


 


 


 


 

 

 


 


 

K

 

6.774

 

0.000

 

0.000

 

6.774

 

0.000

 

0.031

 

0.000

 

0.031

 

2.539

 

0.032

 

0.000

 

2.571

 

K

 

9.313

 

0.063

 

S04

 

5.332

 

0.000

 

0.000

 

5.332

 

0.018

 

0.000

 

0.000

 

0.018

 

2.188

 

0.029

 

0.000

 

2.217

 

SO4

 

7.538

 

0.029

 

Li

 

0.576

 

0.004

 

0.000

 

0.579

 

0.000

 

0.002

 

0.000

 

0.002

 

0.069

 

0.169

 

0.000

 

0.238

 

Li

 

0.645

 

0.174

 

H3BO3

 

1.070

 

0.000

 

0.000

 

1.070

 

0.000

 

0.003

 

0.000

 

0.003

 

0.411

 

0.006

 

0.000

 

0.417

 

B

 

0.259

 

0.002

 

 

Intermediate area (between Mop y Sop geographic limits)

                                         

                                         

 

 

SO4/Mg >1.1 SO4/Mg <= 2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Reserve

 

 

 


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


 

 

 

Proven

 

Probable

 

Err > 35%

 

Total

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Proven

 

Probable

 

 

 


 


 


 


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


 


 

K

 

6.524

 

0.155

 

0.000

 

6.679

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

K

 

6.524

 

0.155

 

S04

 

6.049

 

0.117

 

0.000

 

6.166

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SO4

 

6.049

 

0.117

 

Li

 

0.294

 

0.258

 

0.000

 

0.551

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Li

 

0.294

 

0.258

 

H3BO3

 

1.065

 

0.049

 

0.000

 

1.114

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

B

 

0.186

 

0.009

 

 

   

SOP Area

                                         
   
                                         

 

 

Chemical Parameter SO4/(Mg + 1.75Li) > 1.8
Mg/Li > 6.3 SO4/K > 1.2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Reserve

 

 

 


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


 

 

 

Proven

 

Probable

 

Err > 35%

 

Total

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Proven

 

Probable

 

 

 


 


 


 


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


 


 

K

 

7.982

 

3.011

 

0.000

 

10.993

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

K

 

7.982

 

3.011

 

S04

 

16.862

 

0.000

 

0.000

 

16.862

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SO4

 

16.862

 

0.000

 

Li

 

0.170

 

0.509

 

0.169

 

0.847

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Li

 

0.170

 

0.509

 

H3BO3

 

2.089

 

0.346

 

0.000

 

2.435

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

B

 

0.365

 

0.061

 

 

   

SOP Area

                                         
   
                                         

 

 

Chemical Parameter SO4/(Mg + 1.75Li) > 2.0
Mg/Li < 6.3 SO4/K < 1.2

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Reserve

 

 

 


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


 

 

 

Proven

 

Probable

 

Err > 35%

 

Total

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Proven

 

Probable

 

 

 


 


 


 


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


 


 

K

 

2.479

 

0.048

 

0.000

 

2.528

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

K

 

2.479

 

0.048

 

S04

 

3.015

 

0.000

 

0.000

 

3.015

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SO4

 

3.015

 

0.000

 

Li

 

0.035

 

0.168

 

0.000

 

0.203

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Li

 

0.035

 

0.168

 

H3BO3

 

0.467

 

0.006

 

0.000

 

0.473

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

B

 

0.082

 

0.001

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

TOTAL

 

Reserve

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Proven

 

Proven

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 


 


 


 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

K

 

39.8

 

5.0

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

SO4

 

35.9

 

1.6

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Li

 

2.0

 

1.4

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

B

 

1.1

 

0.2

 

22


 

6.

Process recovery yields

The proven and probable reserves indicated in section 5 do not include adjustments due to evaporation and metallurgical processes, which must be taken into consideration to obtain the ions that will finally become the recoverable reserves.

The yields obtained in the evaporation and metallurgical processes to which the ions are submitted are as follows:

 

 

 

Characteristics

 

Ponds

 

Yield
Plant

 

Other processes

 

Total
Recovery Yield

 

 

 


 


 


 


 


 

K

 

MOP Area

 

82

%

82

%

 

 

67

%

K

 

SOP Area

 

73

%

82

%

 

 

60

%

K

 

SO4/(Mg+1.75Li) >= 1.8, Mg/Li >= 6.3
SO4/K <= 2.0

 

60

%

49

%

 

 

29

%

Li

 

SO4/Mg <= 0.5

 

35

%

83

%

 

 

29

%

Li

 

SO4/Mg > 0.5

 

35

%

83

%

86

%

25

%

SO4

 

SO4/Mg <= 0.5

 

0

%

 

 

 

 

0

%

SO4

 

SO4/Mg > 0.5

 

82

%

55

%

62

%

28

%

SO4

 

SO4/(Mg+1.75Li) >= 1.8, Mg/Li >= 6.3
SO4/K <= 2.0

 

82

%

55

%

62

%

28

%

SO4

 

SO4/Mg > 2.0

 

62

%

55

%

 

 

34

%

B

 

 

 

81

%

37

%

 

 

30

%

Based on these yields, the following recoverable reserves are obtained for each one of the deposits and process chemical parameters, in millions of metric tons:

1) MOP area and SO4/Mg<=0.5:

 

 

 

 

Reserve

 

Recov.
Yield

 

Recoverable reserve

 

 

 

 


 

 


 

 

 

 

Proven

 

Probable

 

 

Proven

 

Probable

 

 

 

 


 


 


 


 


 

 

K

 

7.3

 

0.6

 

67

%

4.9

 

0.4

 

 

SO4

 

0.3

 

0.7

 

0

%

0.0

 

0.0

 

 

Li

 

0.5

 

0.1

 

29

%

0.1

 

0.0

 

 

B

 

0.1

 

0.1

 

30

%

0.0

 

0.0

 

2) MOP area and 0.5< SO4/Mg <=1.1:

 

 

 

 

Reserve

 

Recov.
Yield

 

Recoverable reserve

 

 

 

 


 

 


 

 

 

 

Proven

 

Probable

 

 

Proven

 

Probable

 

 

 

 


 


 


 


 


 

 

K

 

6.2

 

1.1

 

67

%

4.1

 

0.8

 

 

SO4

 

2.2

 

0.8

 

28

%

0.6

 

0.2

 

 

Li

 

0.4

 

0.2

 

25

%

0.1

 

0.0

 

 

B

 

0.1

 

0.0

 

30

%

0.0

 

0.0

 

23


3) MOP area and 1.1< SO4/Mg <=2.0:

 

 

 

 

Reserve

 

 

 

Recoverable reserve

 

 

 

 


 

 

 


 

 

 

 

Proven

 

Probable

 

Recov.
Yield

 

Proven

 

Probable

 

 

 

 


 


 


 


 


 

 

K

 

9.3

 

0.1

 

67

%

6.3

 

0.0

 

 

SO4

 

7.5

 

0.0

 

28

%

2.1

 

0.0

 

 

Li

 

0.6

 

0.2

 

25

%

0.2

 

0.0

 

 

B

 

0.3

 

0.0

 

30

%

0.1

 

0.0

 

4) Intermediate area (between MOP & SOP geographic limits), and 1.1< SO4/Mg <=2.0:

 

 

 

 

Reserve

 

 

 

Recoverable reserve

 

 

 

 


 

 

 


 

 

 

 

Proven

 

Probable

 

Recov.
Yield

 

Proven

 

Probable

 

 

 

 


 


 


 


 


 

 

K

 

6.5

 

0.2

 

60

%

3.9

 

0.1

 

 

SO4

 

6.0

 

0.1

 

28

%

1.7

 

0.0

 

 

Li

 

0.3

 

0.3

 

25

%

0.1

 

0.1

 

 

B

 

0.2

 

0.0

 

30

%

0.1

 

0.0

 

5) SOP area and SO4/(Mg+1.75Li) >= 1.8, Mg/Li>6.3 and SO4/K>1.2:

 

 

 

 

Reserve

 

 

 

Recoverable reserve

 

 

 

 


 

 

 


 

 

 

 

Proven

 

Probable

 

Recov.
Yield

 

Proven

 

Probable

 

 

 

 


 


 


 


 


 

 

K

 

8.0

 

3.0

 

60

%

4.8

 

1.8

 

 

SO4

 

16.9 

 

0.0

 

28

%

4.7

 

0.0

 

 

Li

 

0.2

 

0.5

 

25

%

0.0

 

0.1

 

 

B

 

0.4

 

0.1

 

30

%

0.1

 

0.0

 

6) SOP area and SO4/(Mg+1.75Li) >= 1.8, Mg/Li<=6.3 or SO4/K=<1.2:

 

 

 

 

Reserve

 

 

 

Recoverable reserve

 

 

 

 


 

 

 


 

 

 

 

Proven

 

Probable

 

Recov.
Yield

 

Proven

 

Probable

 

 

 

 


 


 


 


 


 

 

K

 

2.5

 

0.0

 

29

%

0.7

 

0.0

 

 

SO4

 

3.1

 

0.0

 

34

%

1.0

 

0.0

 

 

Li

 

0.0

 

0.2

 

25

%

0.0

 

0.0

 

 

B

 

0.1

 

0.0

 

30

%

0.0

 

0.0

 

24


 

In this way, we can quantify the proven and probable reserves, the recoverable reserves and the average yields for the recovery of each ion as shown in the following table:

 

 

 

 

Reserve

 

Recoverable reserve

 

Average Recovery Yield

 

 

 

 


 


 


 

 

 

 

Proven

 

Probable

 

Proven

 

Probable

 

Proven

 

Probable

 

 

 

 


 


 


 


 


 


 

 

K

 

39.8

 

5.0

 

24.7

 

3.1

 

62

%

62

%

 

SO4

 

35.9

 

1.6

 

10.2

 

0.3

 

28

%

16

%

 

Li

 

 2.0

 

1.4

 

 0.5

 

0.4

 

26

%

26

%

 

B

 

 1.1

 

0.2

 

 0.3

 

0.1

 

30

%

30

%

Justification for the basis we use for distinguishing between proven and probable reserves for our Caliche and Atacama Salar Brines mines

Caliche Ore Mines

The definition of reserves is based on the classification proposed by the Instituto de Ingenieros de Minas de Chile (Institute of Mining Engineers of Chile), which in turn is based on the Australian JORC classification.

We have defined Probable Reserves as the resources obtained by calculations based on drill hole grid patterns having a 200 x 200 meter spacing over the caliche ore. These resource calculations are corrected by factors that take into account mining, metallurgical, and economic parameters, among others. Due to the nature of the caliche ore, which is found in horizontal layers of great extension, the information obtained from the 200 x 200 meter drill hole grid pattern allows us to predict that there is continuity between the characteristics of the individual sampling points in the grid. These reserves are obtained by the evaluation of Polygons, and have an uncertainty or error margin greater than that of proven reserves.

We have defined Proven Reserves as the resources obtained by calculations based on drill hole grid patterns having a 100 x 100 meter and 50 x 50 meter spacing over the caliche ore bodies. These resource calculations are corrected by factors that take into account mining, metallurgical, technical, and economic parameters, among others. Due to the nature of the caliche ore, the 100 x 100 meter and 50 x 50 meter drill hole grid patterns allow us to state that there is reasonable continuity between the characteristics of the individual sampling points in the grid. These reserves are obtained using the Kriging evaluation and the application of operational parameters to obtain economically profitable reserves. These parameters take into account:

25


 

 

 

 

Pedro de
Valdivia

 

María Elena

 

Pampa Blanca

 

Nueva Victoria

 

 

 

 


 


 


 


 

 

NaNO3(%) referential

 

≥ 7,0

 

≥ 7,5

 

≥ 5,0

 

 

 

I2 (ppm) referential

 

≥ 350

 

≥ 400

 

≥ 450

 

≥ 500

 

 

Overburden depth

 

< 3,0 m

 

< 3,0 m

 

< 3,0 m

 

< 3,0 m

 

 

Caliche depth

 

≥ 1,0 m

 

≥ 1,0 m

 

≥ 1,0 m

 

≥ 1,0 m

 

 

Waste/mineral ratio

 

< 1,5

 

< 1,5

 

< 1,5

 

< 1,5

 

 

Clay and fines

 

Low

 

Low

 

Low

 

Low

 

 

SO4 useful

 

< 12%

 

< 12%

 

< 12%

 

< 12%

 

 

Geomechanic Quality

 

Good

 

Good

 

Good to medium

 

Good to medium

 

Resources calculated on the basis of drill hole patterns having a spacing of 400 x 400 meters or more are not considered as reserves.

Exploitable Reserves Factor

In order to express the proven in terms of final exploitable reserves, it is necessary to consider additional operational extraction restrictions; therefore an adjustment is needed for these reserves in order to get a trustworthy approximation of exploitable reserves. This adjustment is effected by multiplying reserves by an empirical historical factor of 80%. Thus, historically exploitable reserves represent 80% of reserves.

The exploitable reserves factor is defined by two main criteria: maximum exploitation base and walls slopes of 4%, and minimum width of exploitation sectors.

Atacama Salar Brines Mines

Definition of Proven and Probable Reserves

The Kriging method assigns an estimation error to each one of the blocks evaluated. This error expresses a percentage of uncertainty in the estimated grade for the point that sustains the block. This uncertainty is calculated according to the variograms, block size, and distance between the samples.

For each one of the chemical ions, proven reserves of the deposit are defined as those blocks that comply with an estimation error of up to 15%. This estimation error is associated to the element or ion under evaluation.

In the case of probable reserves, the selected blocks must comply with an estimation error between 15 and 35%. All those blocks with an error greater than 35% are not considered in this evaluation of reserves.

26


Should you have any question or comments about the responses in this letter, please contact the undersigned at (56-2)-425-2479. Alternatively, please contact Patricio Vargas at (56-2) 425-2274.

 

 

 

 

Very truly yours,

       

 

 

/s/ Ricardo Ramos R.

 

 

 


 Date: January 8, 2007

 

 

Ricardo Ramos R.
Chief Financial Officer

27