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Cross section of Gold Reach's East Seel Project

Gold Reach’s Copper Projects Looking More and More Like Another HuckleBerry

 It appears the deposit was subject to a series of faulting events that displaced portions of the mineralized rock units. The question for the geologists to answer is: Where did the rest of the deposit go?

Disclaimer: This is an editorial review of a public press release and not an endorsement. It may include opinions or points of view that may not be shared by the companies mentioned in the release. The editorial comments are highlighted so as to be easily separated from the release text and portions of the release not affecting this review may be deleted.

VANCOUVER, BRITISH COLUMBIA–(Marketwired – Jan. 6, 2014) – Gold Reach Resources Ltd. (TSX VENTURE:GRV) (Gold Reach and/or the Company) is pleased to announce that assay results for holes S13-170 to 177 from the East and West Seel deposits have been received. The East Seel deposit is located adjacent to the Company’s West Seel discovery, and both occur 4 kilometres south-southwest of the Company’s Ox deposit. All 3 deposits occur on the Company’s 100% owned Ootsa Property located adjacent to the producing Huckleberry copper Mine south of Smithers, British Columbia.

We’ve previously discussed Gold Reach’s Ox Project which is located only 4 km from the East and West Seel Projects and about the same distance from Imperial Metals’ Huckleberry Mine. The projects are all low grade porphyry copper deposits with minor gold, molybdenum and silver and together make up Gold Reach’s Ootsa Property.

Porphyry copper deposits are generally low grade high-tonnage copper deposits.

HIGHLIGHTS

  • East Seel Deposit – High Grade Intercepts Continue
    • Hole S13-172 intersected 35.8m of 0.84% copper equivalent from 39.2 to 75m depth.
    • Hole S13-174 intersected 91.5m of 0.62% copper equivalent from 36.5 to 128m depth, including 53.5m grading 0.76% copper equivalent.
    • Hole S13-175 intersected 46.3m of 0.74% copper equivalent from 101.7 to 148m depth.
    • Hole S13-177 intersected 186.2m of 0.78% copper equivalent from 26.8 to 213m depth, including 82.2m grading 1.15% copper equivalent and 46m of 1.44% copper equivalent.
  • West Seel Deposit – Near Surface High Grade Expanded
    • Hole S13-171 intersected 14m of 0.93% copper equivalent from 7 to 21 metres depth. This extends the near surface high-grade zone 80 metres to the southeast of the high grade intercept encountered in hole S13-169.
    • The West Seel high grade mineralization starts as shallow as 7m below surface and has been outlined over widths up to 150m, a length of up to 125m and a thickness of up to 40m, and remains open for expansion.
  • West Seel Deposit – Long Mineralized Intercepts
    • Hole S13-171 intersected 224m of 0.42% copper equivalent from 7 to 231m depth, followed by another 126m of 0.36% copper equivalent from 261m to the end of the hole at 387m.
    • Hole S13-176 intersected 198m of 0.39% copper equivalent from 44 to 242m depth, followed by another 58.2m of 0.41% copper equivalent from 266m to 324.2m depth.

When discussing grades in mixed metal deposits we often see the grade expressed as an “equivalent”. In this case, the grade is expressed as a copper equivalent. A copper equivalent calculation takes the value of all of the accessory metals such as gold and silver and combines them into a single number representing the equivalent value of a single metal. You can read more about this in our article on mining company drill results or try out our metal equivalent calculator.

The goal of the 2013 drilling program, which is now complete, was to infill and expand known zones of higher-grade near-surface mineralization at Ox, East Seel, and West Seel and the program has been very successful at achieving that goal. Results for 22 additional drill holes from the 2013 program are still pending.

East Seel Drill Results

Drill hole location map for Gold Reach's East and West Seel Projects

Drill hole location map for Gold Reach’s East and West Seel Projects

Holes S13-170 and 172 were drilled on East Seel section 17 NE, the northeastern most section on the East Seel zone, where mineralization is truncated by the North and East Faults. Mineralization on the section occurs below 15 to 35 metres of gravel cover, and is up to 175 meters wide by 200 metres deep. Hole S13-170 intersected 4 zones of mineralization. From the top downwards these are: 15.5 metres grading 0.26% copper and 0.23 g/t gold (0.43% copper equivalent) from 59.4 to 70.4 metres depth, 4.8 metres grading 0.49% copper and 0.53 g/t gold (0.88% copper equivalent) from 76.3 to 81.1 metres depth, 34.5 metres grading 0.36% copper and 0.39 g/t gold (0.65% copper equivalent) from 87.5 to 122 metres depth, and 64 metres grading 0.26% copper and 0.18 g/t gold (0.42% copper equivalent) from 144 to 208 metres depth. Hole S13-172 intersected 95.8 metres grading 0.30% copper and 0.35 g/t gold (0.55% copper equivalent) from 39.2 to 135 metres depth, including 35.8 metres grading 0.45% copper and 0.54 g/t gold (0.84% copper equivalent) from 39.2 to 75 metres depth.

The diagram above shows that the East and West Seel deposits are separated by a structural fault. The East Seel appears to be bound by two other faults. One of the principle jobs of a geologist is to de-construct the chain of events that lead to the emplacement of a mineralized system and effect it after emplacement. In  the case of the East and West Seel projects (and the Ox to the north) it appears the deposit was subject to a series of faulting events that displaced portions of the mineralized rock units. The question for the geologists is: Where did the rest of the deposit go?  

Hole S13-174 was a vertical hole drilled between East Seel sections 16 and 17 NE. The hole intersected 91.5 metres grading 0.36% copper and 0.35 g/t gold (0.62% copper equivalent) from 36.5 to 128 metres depth, including 53.5 metres grading 0.43% copper and 0.45 g/t gold (0.76% copper equivalent) from 36.5 to 90 metres depth.

Hole S13-175 was a vertical in-fill hole drilled on East Seel section 16 NE. The hole intersected mineralization in 5 closely spaced mineralized zones over a cumulative width of 153 metres. The intercepts are summarized in the table below.

Summary of select drill intercepts – East Seel Holes S13-170, 172, 174, 175, 177
Drill Hole From (m) To (m) Width (m)* Cu % Au g/t Ag g/t Mo % Cu Eq.%**
S13-170 59.4 70.4 15.5 0.26 0.23 1.50 0.43
S13-170 76.3 81.1 4.8 0.49 0.53 2.21 0.88
S13-170 87.5 122.0 34.5 0.36 0.39 1.92 0.65
S13-170 144.0 208.0 64.0 0.26 0.18 1.26 0.005 0.42
S13-172 39.2 135.0 95.8 0.30 0.35 1.07 0.55
including 39.2 75.0 35.8 0.45 0.54 1.64 0.84
S13-172 201.0 209.0 8.0 0.52 0.12 15.75 0.74
S13-174 36.5 128.0 91.5 0.36 0.35 1.45 0.62
including 36.5 90.0 53.5 0.43 0.45 1.60 0.76
S13-175 73.0 85.1 12.1 0.22 0.32 1.00 0.45
S13-175 91.4 98.0 6.6 0.41 0.54 2.56 0.81
S13-175 101.7 148.0 46.3 0.33 0.56 2.08 0.74
S13-175 198.0 230.0 32.0 0.27 0.07 9.04 0.40
S13-175 246.0 302.0 56.0 0.27 0.09 6.77 0.39
S13-177 26.8 213.0 186.2 0.39 0.53 1.86 0.78
including 26.8 109.0 82.2 0.56 0.81 2.43 1.15
including 61.0 107.0 46.0 0.68 1.05 2.73 1.44
S13-177 261.0 283.0 22.0 0.24 0.23 1.17 0.41
*Width refers to drill hole intercepts, true widths have not been determined.
**Cu Eq. (copper equivalent) has been used to express the combined value of copper, molybdenum, gold and silver as a percentage of copper, and is provided for illustrative purposes only. No allowances have been made for recovery losses that may occur should mining eventually result. Calculations use metal prices of US $2.50/lb copper, $1200/oz gold, $15 silver, and $10/lb molybdenum using the formula Cu Eq.% = Cu% + (Au g/t x 0.701) + (Ag g/t x 0.0087) + (Mo% x 4.01).

 

Note the disclaimer which explains how the company calculated its copper equivalent. In early stage reporting equivalents generally assume a 100% metal recovery. Commodity prices must also be factored into the calculations and the prices used can effect the result dramatically, especially if the value of one or more commodities is over or under-weighted in the calculation.

What’s interesting about the East Seel results is that they contain almost no molybdenum. Compare that to West Seel, the Ox and the Huckleberry mine which all show consistent low-grade moly. The geology on either side of the West Seel fault is clearly different and further demonstrates that portions of the deposit have been physically displaced through fault movement. The cross-section diagrams below illustrate this more clearly.

Cross section of Gold Reach's East Seel Project showing mineralized units truncated by the East fault

Cross section of Gold Reach’s East Seel Project showing mineralized units truncated by the East fault

Cross section of Gold Reach's West Seel Project showing mineralized units truncated by the West Seel fault

Cross section of Gold Reach’s West Seel Project showing mineralized units truncated by the West Seel fault

 

 

 

 

 

 

 

 

 

 

Hole S13-177 was a vertical in-fill hole drilled between East Seel sections 15 and 16 NE. The hole intersected 186.2 metres grading 0.39% copper and 0.53 g/t gold (0.78% copper equivalent) from 26.8 to 213 metres depth, including 82.2 metres grading 0.56% copper and 0.81 g/t gold (1.15% copper equivalent) from 26.8 to 109 metres depth, and 46 metres grading 0.68% copper and 1.05 g/t gold (1.44% copper equivalent) from 61 to 107 metres depth. Hole S13-177 confirms the continuity of the high grade core between previously released intercepts in hole S13-148 (146.3m grading 0.51% copper and 0.59 g/t gold (0.94% copper equivalent) including 44.3m grading 0.94% copper and 1.12 g/t gold (1.76% copper equivalent)) and hole S13-155 (238m grading 0.38% copper and 0.47 g/t gold (0.73% copper equivalent) including 160m grading 0.44% copper and 0.53 g/t gold (0.83% copper equivalent)).

Perhaps it would’ve been better to use the word “shell” rather than “high grade core” in the above paragraph. The core of porphyry systems tend to be composed of low grade or barren material. Gold Reach is probably referring to one of the high grade ore shells which typically exist on the margins of porphyry systems.

West Seel Drill Results

Holes S13-171 173, and 176 are located at the West Seel deposit and are the last of the holes drilled into the West Seel deposit during 2013.

The hole intersected 224 metres grading 0.21% copper, 0.14 g/t gold, 5.13 g/t silver, and 0.017% molybdenum (0.42% copper equivalent) from 7 to 231 metres depth, including 14 metres grading 0.25% copper, 0.76 g/t gold, 8.06 g/t silver, and 0.018% molybdenum (0.93% copper equivalent) from 7 to 21 metres depth. Hole S13-171 also intersected an additional 126 metres grading 0.20% copper, 0.11 g/t gold, 1.88 g/t silver, and 0.017% molybdenum (0.36% copper equivalent) from 261 to the end of the hole at 387 metres depth. On Section 8.5 NE mineralization has been defined over a width of 300 metres and remains open to the southeast, and to depths of over 500 metres and remains open at depth. Additional drilling is required in this area to fully define the extent of mineralization.

Hole S13-173 intersected 3 zones of significant mineralization as summarized in the table below. Hole S13-176 intersected 198 metres grading 0.21% copper, 0.12 g/t gold, 4.96 g/t silver, and 0.013% molybdenum (0.39% copper equivalent) from 44 to 242 metres depth, followed by another 58.2 metres grading 0.19% copper, 0.21 g/t gold, 2.29 g/t silver, and 0.012% molybdenum (0.41% copper equivalent) from 266 to 324.2 metres depth.

The high grade intercept in hole S13-171 is part of a larger zone of near-surface higher-grade mineralization at the West Seel zone that has now been intersected in holes S12-108, S13-150, S13-154, S13-156, S13-167, S13-169 and S13-171. This higher-grade zone starts as shallow as 7 metres below surface and has widths up to 150 metres, a length of up to 125 metres and a thickness of up to 40 metres. Thicknesses of drill intersections within this zone range from a low of 14 metres grading 0.93% Cu Eq. (0.25% Cu, 0.75 g/t Au, 8.06 g/t Ag, and 0.018% Mo) in hole S13-171, to 26 metres grading 1.5% Cu Eq. (0.92% Cu, 0.42 g/t Au, 28.19 g/t Ag, 0.009% Mo) in hole S13-169, to a high of 40 metres grading 0.85% Cu Eq. (0.28% Cu, 0.64 g/t Au, 8.98 g/t Ag, 0.012% Mo) in hole S13-156. Further drilling will be required in 2014 to fully understand the extent of this near-surface higher-grade zone which sits above and within a much larger mineralized body that includes intercepts such as 316 metres grading 0.56% Cu Eq. (0.28% Cu, 0.23 g/t Au, 5.28 g/t Ag, and 0.018% Mo) in hole S12-108 and 355 metres grading 0.48% Cu Eq. (0.22% Cu, 0.19 g/t Au, 4.47 g/t Ag, and 0.021% Mo) in hole S13-167. This large zone of mineralization at West Seel is being evaluated as an open pit target.

Summary of select drill intercepts – West Seel Holes S13-171, 173, and 176
Drill Hole From (m) To (m) Width (m)* Cu % Au g/t Ag g/t Mo % Cu Eq.%**
S13-171 7.0 231.0 224.0 0.21 0.14 5.13 0.017 0.42
including 7.0 21.0 14.0 0.25 0.76 8.06 0.018 0.93
S13-171 261.0 387.0 EOH 126.0 0.20 0.11 1.88 0.017 0.36
S13-173 82.0 108.0 26.0 0.25 0.18 5.65 0.013 0.48
S13-173 152.0 278.0 126.0 0.19 0.09 4.78 0.017 0.36
S13-173 310.0 405 EOH 95.0 0.18 0.10 2.95 0.017 0.34
S13-176 44.0 242.0 198.0 0.21 0.12 4.96 0.013 0.39
S13-176 266.0 324.2 58.2 0.19 0.21 2.29 0.012 0.41
*Width refers to drill hole intercepts, true widths have not been determined. EOH = end of hole.
**Cu Eq. (copper equivalent) has been used to express the combined value of copper, molybdenum, gold and silver as a percentage of copper, and is provided for illustrative purposes only. No allowances have been made for recovery losses that may occur should mining eventually result. Calculations use metal prices of US $2.50/lb copper, $1200/oz gold, $15 silver, and $10/lb molybdenum using the formula Cu Eq.% = Cu% + (Au g/t x 0.701) + (Ag g/t x 0.0087) + (Mo% x 4.01).

 

Compared to East Seel, the West Seel results are lower grade, but with much longer intervals and more consistent grades. The question is whether these grades could be considered economic. Grades above 1% are normally the target for a profitable for a open pit copper mine, however the nearby Huckleberry open pit copper mine has an average grade of 0.334% Cu  and 0.009% Mo with cut-off grades ranging from 0.15% to 0.20% Cu. If Huckleberry is the benchmark, then Gold Reach is looking pretty good.

Drilling Update

The 2013 drill program is now complete. Assay results for the first 31 holes drilled at Seel have been received (holes S13-147 to 177) and released. An additional 22 holes have been completed at Seel (S13-178 to 199) and will be released shortly.

About Gold Reach Resources

The Ootsa property is an advanced stage exploration project containing the Seel and Ox porphyry systems both with compliant resource estimates open for expansion. The Company has completed 134,878 metres of core drilling on the property, with 36,135 meters completed during 2013. An updated resource for the Ox deposit is expected shortly and an updated resource on the Seel deposit is expected in the first quarter of 2014.

QA/QC is an important part of a drill program. Read about QA/QC for geochemical results.

Quality Control

All drill core is logged, photographed, and cut in half with a diamond saw. Half of the core is bagged and sent to AGAT Laboratories for analysis (which is an ISO 9001 and ISO/IEC 17025 certified lab), while the other half is archived and stored on site for verification and reference purposes. Gold is assayed by standard fire assay methods with 45 additional elements analyzed by Induced Coupled Plasma (ICP) utilizing a 4-acid digestion. Duplicate samples, blanks, and certified standards are included with every sample batch and then checked to ensure proper quality assurance and quality control.

 

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Geology for Investors seeks to demystify mineral exploration and mining projects for mining company investors. All of our writers and contributors are experienced and educated in geology and the geosciences.