YeOldGoldNugget's Blog Spot: January 2005

Saturday, January 1, 2005

Quality Assurance / Quality Control Procedures for the Drilling Program at La Preciosa

By 79Atoms on Saturday, January 01, 2005

Sound QA/QC procedures are important both for the company to know what is happening with the samples and for the investors to know that industry "Best Practices" are being met or exceeded.
The following points illustrate the path samples follow from initial core drilling to final announcement of results:

On The Property

1. Drill hole locations are laid out in the field by Orko geologists. Pad construction is supervised and fore-sight / back-sight markers are set to align the direction of drilling.

2. Drilling is being conducted by Major Drilling de Mexico, a subsidiary of Major Drilling Group International Inc., with experienced drillers. They are using two rigs on La Preciosa, a Longyear-44 and a Longyear-38. The diamond drill core is HQ diameter for the total length of the drilling with the Longyear-44. For the Longyear-38, holes start with HQ and reduce to NQ at approximately 260 metres depth. Both of these drill core sizes provide a large sample as recommended for the testing of precious metal deposits.

3. Down-hole surveys are conducted at 50 metre intervals down the drill hole using a Reflex survey device to measure azimuth and dip of the hole.

4. It is the driller's responsibility to insure that the core in the boxes is in the correct order and to mark the length tags for each rod-length of core, as well as mark the inside of the core boxes where the tag is located.

5. Core boxes are picked up from the drill site by Orko personnel and taken to the drill core logging facilities on the property.

6. Boxes are then laid out on logging tables and checked to make sure that the core is continuous and in the right order in each box. Core boxes are cleaned at this stage to remove drill grease.

7. Measurements of core between rod-length tags are taken to determine drill core recovery.

8. The proportions of core fragments greater than 10 cm and 20 cm in length are determined to obtain RQD values. This data is entered into an RQD log. While this information will not be used in the exploration stage, it will be valuable information for future mine design indicating where competent ground and broken ground conditions can be expected.

9. All core boxes and lids are then clearly labelled with the "from" and "to" lengths in metres.

10. Geological logging of the core is conducted and sample positions are marked to conform with lithological/alteration changes. Sample numbers are written inside of the core boxes corresponding to pre-printed sample tags.

11. Chalk lines are marked down the axis of the core and the boxes for sampling are moved to the cutting area. Diamond saw blade cutters are used to cut the core in half. This method is preferred over core splitters for precious metal deposits.

12. The core boxes are returned to their places in order on the logging tables. Strong plastic rock sample bags are labelled with sample numbers on the outside and the sample tags inserted inside, then ½ the core is placed in their respective sample bags.

13. The boxes from which samples have been taken are marked with a red asterisk and placed in sequence on the metal core racks.

14. The sample bags are moved to the testing table for determination of specific gravity. An SG value is determined for every sample and samples with high sulphide and/or barite content, or possessing vugs, are tested twice to confirm higher or lower SG readings. This information is used when determining tonnage.

15. Standards are weighed and inserted every 10th sample. Standards Orko-1 and Orko-3 were made from ore-grade material from the stockpile. Standards Orko-2 and Orko-4 were made from barren basaltic rock and represents a blank value.

16. Sample bags are then closed and inserted in large sacks. These sacks are labelled with the sample range and company name, with the laboratory instruction sheet placed in sack #1 of the sampling batch.

Laboratories

The city of Durango, Mexico, is fortunate to have the services of several analytical laboratories, including the certified labs SGS Mineral Services and Inspectorate. Depending on the work loads of the labs, batches can be sent to either lab. SGS Lab in Durango

17. The sacks of samples are delivered by Orko personnel to the preparation laboratory of SGS Mineral Services in Durango, Mexico.

18. From this point onward, SGS takes responsibility for the samples. SGS is an accredited and well respected analytical company. The Durango lab is where the samples are crushed and a sub-sample is pulverized. The pulverized pulp is placed in kraft sample bags and the un-pulverized portions are returned to the original sample bags.

19. Batches of the sample pulps are shipped by DHL couriers to the Toronto, Canada laboratories of SGS. Orko personnel pick up the remainder of the crushed samples, referred to as "sample rejects", which are taken back to La Preciosa for storage. The sample rejects are thus available for re-testing when required.

SGS Lab in Toronto, Ontario, Canada

20. In Toronto, the sample pulps are analysed by Inductively Coupled Plasma (ICP) for 40 elements. Gold is tested by Fire Assay and silver is tested by Atomic Absorbtion Spectrometry (AAS). Each method has a lower and upper calibration range for which the results are accurately determined.

21. Sample results falling out of the calibration range for the elements Au, Ag, Pb, Zn, Cu and Ba are re-analysed by methods with higher calibration ranges. This is true for silver >300 g/t, gold >10 g/t, and Pb, Zn, Cu and Ba >10,000 ppm.

22. SGS also performs a "duplicate analysis" on every 12th sample, insuring that there is at least one duplicate run with every batch.

Inspectorate Lab in Durango

23. Near the end of 2006, Inspectorate established a new preparation lab in Durango, with a 700 sample-per-run drying oven. Inspectorate is an accredited and well respected analytical company, thus Orko has added Inspectorate to the list of analytical service providers. The sacks of samples are delivered by Orko personnel to the preparation laboratory of Inspectorate Labs in Durango, Mexico.

24. From this point onward, Inspectorate takes responsibility for the samples. The Durango lab is where the samples are crushed and a sub-sample is pulverized. The pulverized pulp is placed in kraft sample bags and the un-pulverized portions are returned to the original sample bags.

25. Batches of the sample pulps are shipped by courier to the Sparks, Nevada, USA laboratories of Inspectorate. Orko personnel pick up the remainder of the crushed samples, referred to as "sample rejects", which are taken back to La Preciosa for storage. The sample rejects are thus available for re-testing when required.

Inspectorate Lab in Sparks, Nevada, USA

26. In Sparks, the sample pulps are analysed by Inductively Coupled Plasma (ICP) for 30 elements. Gold and silver are tested by Fire Assay (FAA). Each method has a lower and upper calibration range for which the results are accurately determined.

27. Sample results falling above the calibration range for the elements Au, Ag, Pb, Zn, Cu and Ba are re-analysed by methods with higher calibration ranges. This is true for silver >200 g/t, gold >10 g/t, and Pb, Zn, Cu and Ba >10,000 ppm.

28. Inspectorate also performs a "duplicate analysis" on every 15th sample, insuring that there is at least one duplicate run with every batch.

Orko in Vancouver and Durango

29. Results are tabulated on spreadsheets and e-mailed to Orko geologists. Originals of the assay certificates are sent in hard-copy format to Vancouver.

30. Upon receiving the completed analytical results, geologists then extract the duplicate and standard samples for examination of expected values versus tested values.

31. The spreadsheet information for the drill hole samples is then matched with the sampling intervals and geological observations for interpretation.

32. Results of the merged data are then sent to Orko management, along with the interpreted true width of the structures.

33. Orko management periodically prepares news releases to make public the information from the drilling in a format compatible with NI 43-101 standards. A "Qualified Person" signs-off on news releases containing technical data.

YeOldGoldNugget's links of interest

San Juan

By 79Atoms on Saturday, January 01, 2005

April 01, 2008.

Summary

click to download in pdf.

The San Juan property is 24,580 hectares and is located North-West from La Preciosa Project. The company has an option agreement with Silver Standard Resources Inc. (NASDAQ: SSRI) to earn a 75% interest, by expending US$750,000 on exploration. Thus far, three silver-gold epithermal veins have been located; La Plomosa, El Vaquero and San Juan veins are known to outcrop on this property.

Objective

To locate a similar vein system like Abundancia, La Gloria and Martha on the La Preciosa Project.

Strategy

First Step: Regional sampling survey, geological mapping (completed)

Second Step: Trenching (completed)

Third Step: Diamond drill program of the initial target areas, 8 diamond holes completed in late 2007 on the La Plomosa vein, results pending.

A continuation drilling program is expected to commence in the near future to test the El Vaquero vein structure.

YeOldGoldNugget's links of interest

Santa Monica

By 79Atoms on Saturday, January 01, 2005

April 01, 2008.

Summary

click to download in pdf.
Santa Monica is adjacent to the La Preciosa project optioned by Orko from GoldCorp Inc. The Santa Monica Property covers over 17,285 hectares and is located approximately one hour and a half away by paved road from the City of Durango, in Durango State, Mexico. Currently, interpretation of recently completed field programs is underway.

Objective

To Locate a vein system like San Sebastian Mine (Hecla Au-Ag mine)

Strategy

First Step: Regional quartz float sampling survey (Completed)

Second Step: Local grid Geological Mapping, geochemical sampling (Completed)

Third Step: Diamond drill program of initial target areas (Planned)

Available Data: Geophysical survey (I.P.); soil sample results, geological maps

A drilling program is expected to commence in the near future to test anomalous areas developed from the geophysical surveys, geochemical sample and geological mapping.

San Sebastian Mine
Discovery Method:

Regional quartz float sampling survey

Local grid each 25 meters sampling trenches

Diamond drill program of initial target areas (70 ddh)

Annual Production: 80,000 oz Au Eq.
Cut-off: 4 gr.
Recovery: Ag 90%, Au 96%
Average Grade: 17 gr Au Eq.
Staff: 150 people (included 12 geologists)

YeOldGoldNugget's links of interest

La Preciosa

By 79Atoms on Saturday, January 01, 2005

Feb 26, 2009

Summary

Orko Silver controls 100% of its La Preciosa project.
click to download in pdf.

Orko Silver Corp. (under previous name "Orko Gold Corporation") entered into an option agreement in late 2003 with two companies under the direction of Luismin S.A. de C.V., now a part of Goldcorp Inc., to acquire an interest in the La Preciosa silver-gold prospect. A news release, dated 4 March 2006, states that Orko has reached an earn-in position and by agreement has 100% of La Preciosa, with Goldcorp holding an equity interest in Orko.

La Preciosa property is located in Durango State, 47 km northeast of the city of Durango. It consists of a block of mineral exploitation concessions covering 1,134 hectares located southeast of the village of Francisco Javier Mina, northwest of the village of Francisco I. Madero and east of the village of Ricardo Flores Magon. The larger adjacent properties of Santa Monica (17,285 hectares) and San Juan (24,580 hectares) are also under option agreements with Goldcorp and Silver Standard respectively.

La Preciosa property covers Tertiary aged gold and silver bearing epithermal quartz veins, with barite and lesser quantities of base metals, primarily zinc and lead. There are three major vein and vein-breccia systems exposed on a series of hills and ridges, separated by flat floored valleys roughly 800 m wide. The main vein system consists of northward striking and westward dipping veins, plus east striking south dipping cross-cutting veins. The eastern vein-breccia system (Zona Oriente) strikes northwest. Two systems may intersect to the north beneath younger basalt. To the west of these is a third sub-parallel vein system, with north and northwest trending veins, dipping to the west.

La Preciosa veins are composed of poly-phase veins of quartz, often banded, smoky, chalcedonic and amathystine, with a substantial amount of barite laths. Sulphide mineralization is scarce on surface and in the shallow underground workings. Drill core contains disseminated sphalerite, galena, pyrite and acanthite, plus iron and manganese oxides. Wall rocks adjacent to the veins are silicified, particularly between the prominent veins La Gloria and Abundancia. Kaolinite and hematite alteration is common, as well as more distal propylitic chlorite, epidote and pyrite.

The oldest rocks, found only in deeper drill core, consist of Jurassic-Cretaceous graphitic schist, chlorite schist and layers of quartzite. Above the metamorphic units is a thick package of Cretaceous polymictic conglomerate, with lenses of arkosic sandstone. This sedimentary package is topped by Tertiary andesite tuff and andesite agglomerate of the regional Lower Volcanic Sequence. No rhyolites of the Upper Volcanic Sequence are found in the immediate study area, but can be seen on cliffs further to the west. The conglomerates and andesitic rocks are the main host rocks for the veins, but mineralization also extends into the metamorphic rocks. There are a few dioritic dykes in deeper core, but intrusive rocks are generally rare. The youngest unit comes from several Quaternary volcanic vents which erupted basalt flows, filling the lower valleys.

Multiple veins in the main structural zone of La Preciosa ridge have been traced on surface for over 5 kilometres and drilling has revealed that the veins continue to the north beneath the basaltic cover. The veins are also interpreted to extend further south of known exposures. Individual veins have been traced for up to 1.6 km. Of the entire structural zone, the Abundancia and La Gloria veins, plus more recently the Martha vein, have been explored in the greatest detail. The Abundancia and La Gloria veins coalesce at depth, the merged vein is known as the Abundancia vein. There are 2.5 km of underground drifts, following the Abundancia and La Gloria veins, as well as a small portion of the Transversal vein. The original workings are over 100 years old, however, about 60% of the drifts were enlarged and resampled 26 years ago by Luismin. There is a winze that leads down to workings 50 metres below the main 2065 level in Abundancia vein. There are also several raises and small stopes which break through to surface on the Abundancia and La Gloria veins above the 2065 level. At the farthest south exposures, El Orito vein was drifted upon for several hundred metres over a century ago, but has had no modern exploration.

Seven diamond drill holes, totaling 1,319 metres, were drilled by Luismin in a 1981-1982 program. The group of holes were mainly collared west of the Abundancia and La Gloria veins to test a 400 metre strike length of the veins roughly 50 to 75 metres below the 2065 level. The best intercept was from BP-1, which hit a true width of 13.6 metres at 232.0 g/t Ag and 0.10 g/t Au. Hole BP-7 was a longer hole which tested Abundancia and La Gloria veins and also intercepted the sub-parallel Luz Elena vein at greater depth. The 1981-1982 drill program was terminated due to falling metal prices at that time. Core from Luismin's program was split and the remaining half is intact and stored on site.

A single 313 metre hole was drilled by Luismin in the eastern vein-breccia system in 1994. The hole intersected a series of variable silicified zones and veinlet stockwork anomalous in Ag, Au, Pb, Zn and Hg, but did not pass through the complete structure.

In the 1980s, Luismin staff prepared several preliminary resource estimates, which were in-house and do not meet the current NI 43-101 reporting requirements for disclosure of Reserves and Resources. The studies showed a general "Resource" in all categories of approximately 320,000 tonnes in the Abundancia and La Gloria veins grading 238 g/t Ag, 0.70 g/t Au and 0.17 % Pb. The "Proven and Probable Reserves" stood at 30,000 tonnes grading 319 g/t Ag, 1.0 g/t Au, with 0.55 % Pb and Zn combined. These estimates do not follow the requirements for reserves and resources outlined in NI 43-101 as they were estimated prior to the enactment of NI 43-101, however, they have been obtained from sources believed reliable. The resource estimates are considered to be historic, are relevant, but have been replaced by recent estimates utilizing much more drilling data and using current CIM terminology.

In June of 2004, Orko commenced a geological mapping and sampling program on La Preciosa. This was followed by a 40 line-km geophysical survey of Induced Polarization in the northern part of the property in January 2005, performed by SJ Geophysics under Orko's guidance. Orko commenced diamond drilling in March 2005 by Major Drilling International on La Preciosa Ridge, targeting Abundancia and La Gloria, but also extending to Luz Elena vein. The first 24 drill holes were completed by late October 2005 totaling 10,259 metres of diamond drill core.

Favourable results from drilling and interpretation of distinct mineral-shoots within the Abundancia and La Gloria veins gave reason for Orko to make a first resource estimate for the property. Using a cut-off grade of 150 g/t silver-equivalent, Inferred Resource Estimate I totaled 2.72 million tonnes grading 227.2 g/t Ag and 0.462 g/t Au for a silver-equivalent grade of 255.0 g/t. Resource Estimate I was released on 19 January 2006 (Gunning and Whiting, 2006).

Drilling continued and Inferred Resource Estimate II was released on 7 September 2006. This estimate was up to hole BP06-38 for a total of 16,334 metres in La Preciosa Ridge area, including Abundancia, La Gloria and Abundancia Zona Sur veins. Using a cut-off grade of 100 g/t silver-equivalent, Inferred Resource Estimate II totalled 4.05 million tonnes grading 207.4 g/t Ag and 0.384 g/t Au for a silver-equivalent grade of 230.4 g/t. Alternatively, at a 150 g/t cut-off, Inferred Resource Estimate II totalled 3.42 million tonnes grading 235.0 g/t Ag and 0.435 g/t Au for a silver-equivalent grade of 261.1 g/t.

Drilling continued and Inferred Resource Estimate III was released on 13 March 2007. Inferred Resource Estimate III -- At 100 g/t Ag-Eq cut-off the estimate is 5.72 million tonnes grading 192.9 g/t Ag and 0.345 g/t Au, for a silver-equivalent of 213.6 g/t. At 150 g/t Ag-Eq cut-off the estimate is 4.39 million tonnes grading 229.9 g/t Ag and 0.396 g/t Au, for a silver-equivalent of 253.7 g/t.

Drilling continued and Inferred Resource Estimate IV was released on 1 October 2007. Inferred Resource Estimate IV -- At 100 g/t Ag-Eq cut-off the estimate is 10.36 million tonnes grading 199.7 g/t Ag and 0.328 g/t Au, for a silver-equivalent of 219.4 g/t. At 150 g/t Ag-Eq cut-off the estimate is 6.88 million tonnes grading 256.6 g/t Ag and 0.387 g/t Au, for a silver-equivalent of 279.8 g/t.

Drilling continued and Inferred Resource Estimate V was released on 31 March 2008. Inferred Resource Estimate V -- At 100 g/t Ag-Eq cut-off the estimate is 15.35 million tonnes grading 190.0 g/t Ag and 0.321 g/t Au, for a silver-equivalent of 209.2 g/t. At 150 g/t Ag-Eq cut-off the estimate is 6.88 million tonnes grading 256.6 g/t Ag and 0.387 g/t Au, for a silver-equivalent of 279.8 g/t.

The Company's Resource Estimate VI was released Feb 18, 2009 is based the results all the holes drilled to date including the 2008 drilling of an additional 205 holes (79,021m) that was completed after the date of the last resource estimate. The La Preciosa deposit now comprises 47% Indicated Resources and 53% Inferred Resources. Current Indicated Resources are 10.64 million tonnes grading 0.27 g/t Au and 185 g/t Ag for a Silver-Equivalent grade of 201 g/t. at a cut off grade of 100 g/t. The contained metal equals 63.2 million ounces of Silver and 94,000 ounces of Gold for a Silver Equivalent of 68.9 Million Ounces. Current Inferred Resources are 12.0 million tonnes grading 0.25 g/t Au and 185 g/t Ag for a Silver-Equivalent grade of 200 g/t. at a cut off grade of 100 g/t. The contained metal equals 71.8 million ounces of Silver and 97,000 ounces of Gold for a Silver Equivalent of 77.6 Million Ounces.*

In total, eight veins were modeled for the new estimate including the Martha Vein, which dominates the resource. In the process of modeling, lithological units were differentiated which helped in establishing the orientation and continuity of the individual veins. Using geological data along with the metal grades, it was possible to establish continuity of mineralized zones of stockwork, breccia, veins, and veinlets. The high-grade veins within these zones were segregated and modeled. All zones and veins were modeled into a three dimensional solid. Once defined, statistics of each domain and each vein were evaluated separately, and capping was carried-out individually for each vein and domain. The sample data was then composited to three-metre intervals. Grade continuity was evaluated separately for each vein and domain. Inverse distance squared estimation was used. A cut-off grade of 100 g/t was selected by MDA. Classification into Indicated and Inferred was dependent upon the vein continuity, geological continuity and proximity to the closest drill hole, as well as the number of samples and the number of drill holes used in the individual blocks.
All reported resources lie within the modeled veins. The QA/QC work demonstrates reliability of the analytical data and the auditing of the database has shown it is accurate.

* The six resource estimates are all undiluted using a 60:1 gold to silver ratio with no metallurgical extractive factors applied.
Average drill hole spacing is approximately 100 metres for all the holes drilled from 2005-2008. For the 1981-82 program, analytical testing was performed in the Luismin Labs in Durango, Mexico. All 2005-2008 analytical testing has been done by SGS or Inspectorate laboratories, North American based labs both containing ISO certification.

The Martha vein, first identified in hole BP06-77, represents the most significant new target. It is relatively flat lying, dipping an average of 20 degrees to the west. It has a known lateral extent of over four kilometres and varies in widths between 200m to 1.7 kilometres. The Martha vein varies in thickness from one meter to sixty meters and averages about 15. Within that are one or more veins or vein breccias which contain the resource grade material and which average about five meters.

Orko has conducted geological mapping, geophysical testing and has systematically drilled a portion of the known strike length of epithermal silver-gold veins on the property. Two of the veins, La Gloria and Abundancia, were drill tested each along 1.2 km strike length to establish veins on "La Preciosa" which have been traced for five kilometres north-south, as well as multiple east-west veins. Some of the veins include Abundancia, La Gloria, Luz Elena, Carmen, Esperancita, Transversal, Incognita, Nueva, Sur, Ramal Sur, El Orito, Nancy, etc. The Martha Vein has been the focus of drill testing since its discovery in 2007.

The resource estimate results are considered highly favourable by Orko's management. In-fill drilling will be completed by the Company to further increase the confidence in the La Preciosa deposit and to move more of the inferred and Indicated resources into higher resource categories. Expanding Martha vein along strike and at depth, as well as drill testing additional north-south and east-west veins located in the immediate vicinity of the Martha vein, are the main targets.