The mining newspaper for Alaska and Canada's North
The mining newspaper for Alaska and Canada's North
Constantine builds on debut resource at Palmer, readies gold properties for drilling
Constantine Metal Resources Ltd. kicked off 2010 by presenting a debut resource estimate for its Palmer copper-zinc-gold-silver project in Southeast Alaska.
Based on 32 holes drilled into the RW and South Wall zones of the property's Glacier Creek prospect through 2009, an inferred resource of 4.12 million metric tons grading 2.01 percent copper, 4.79 percent zinc, 0.30 grams per metric ton gold and 31 g/t silver (using an NSR cut-off of US$75/t) has been calculated for the property.
"Palmer represents an early stage discovery where Constantine has been able to rapidly define a significant resource with relatively few drill holes," said Constantine President and CEO Garfield MacVeigh.
While two rigs drilled some 7,500 meters through the multiple strata of volcanic massive sulfide mineralization at RW and South Wall, geophysical surveys investigated the larger potential of the mineral-rich, mountainous terrain.
As exploration continues to unlock Palmer's potential, the explorer is stepping up investigations of its gold properties in Ontario and British Columbia.
"Because of the major discovery made at Palmer, Croesus and our other gold projects haven't received the attention they deserved over the past two years, but now with gold up over US$1,200 an ounce we are gearing up to get more aggressive on these projects," Constantine Vice President of Exploration Darwin Green told Mining News.
Expanding Glacier Creek
There are at least three separate stacked layers of mineralization at Glacier Creek. In the South Wall these parallel zones are steep-dipping. At the upper extent of South Wall a fault cuts and folds the three layers at which point they lay into a more horizontal orientation. South Wall Zone 2 and Zone 3 are of the same age strata as the two zones drilled at RW, the flat lying limb of the mineralization.
"There are five separate zones included in the resource, all of which are open for expansion. Drilling has primarily focused on expanding theses zones along strike and to depth. We believe there exists significant potential to find a deeper zone on the upright fold limb below the RW horizon that equates with South Wall Zone 1, and are also trying to direct some of our exploration effort to gain a better understanding of this setting which has seen virtually no drilling to date," Green explained.
Two of the initial holes of the 2010 program, CMR10-33 and CMR10-35, focused on expanding the RW Zone toward to the northwest of hole CMR07-07, which intersects 14 meters of high-grade copper and zinc mineralization.
Hole 35, collared about 45 meters along strike to the west-northwest of CMR07-07, cut 7.1 meters averaging 2.10 percent copper, 1.52 percent zinc, 0.18 grams per metric ton gold and 16.8 g/t silver.
Hole 33, about 60 meters north of hole 7, did not find massive sulfides, but instead broad zones of footwall stringer mineralization containing anomalous zinc were intersected. Similar stringers were cut below the VMS in hole 35 and are helping vector the drilling toward the RW Zone.
Geophysics seek new targets
The geophysical work at Palmer included 40 line-kilometers of surface-based electromagnetic surveys covering areas immediately along trend from the currently defined deposit and several other well mineralized prospects known to occur along a 15-kilometer-, or 9-mile-, long trend on the property.
Constantine drilled one target turned up with the geophysical program.
"The target is about 500 meters north of the Little Jarvis surface showing where chip samples by Kennecott in the mid-1990s returned 4.6 meters grading 13 percent zinc, 7 percent copper and 7 oz/ton silver. Little Jarvis is on the opposite side of the mountain, about 1 kilometer, west of our South Wall drilling," Green said.
Mount Henry Clay, the source of enormous high-grade boulders that occur near the limits of a stranded glacier, is another of the prospective areas Constantine investigated with a geophysical survey this summer.
"We have got some interesting data that has come out of that as well," Green informed Mining News.
Twenty-six samples of various boulders collected by the U.S. Bureau of Mines at the toe of a small ice sheet near Mount Henry Clay returned an average grade of 19.3 percent zinc, 1 percent copper, 0.4 percent lead, 38.2 g/t silver, 0.22 g/t gold and 20.6 percent barium. The source of these boulders has yet to be discovered.
High-grade Ontario gold
When the exploration season at Palmer comes to a close, Constantine will resume its investigation of its Munro-Croesus gold property, a 1,028-acre land package that covers the legendary Croesus gold mine located 75 kilometers, or 47 miles, east of Timmins, Ontario.
For about four years, starting in 1915, miners extracted extremely high-grade gold from Croesus, the richest of which was shipped directly to the Royal Canadian Mint for processing. In 1919 the Ontario Bureau of Mines reported that "765 pounds of ore taken from a portion of the shaft yielded $47,000 worth of gold." At the US$20.67 per troy ounce gold price of the day this would have represented a grade of 203,771 g/t gold.
The Ontario Department of Mines reports that the ore milled at Croesus produced 14,854 ounces gold from 5,333 short tons, for an average grade of 2.78 ounces gold per short ton, or 95.3 grams per metric ton. This does not include the highest grade ore, which was shipped directly to the Royal Canadian Mint.
The historical miners chased the bonanza-grade mineralization to a fault. Recent drilling by Constantine has identified gold-bearing veins on the offset side of the fault and new vein systems at depth below the historic mine workings.
"Garfield has a long family history with the Croesus and has probably done some of the best volcanic stratigraphy mapping of any area in the Abitibi to resolve the structural and stratigraphic setting of the Croesus high-grade, so our target is really well set up," Green said.
The Abitibi gold belt, which has produced some 170 million metric tons of gold since 1901, is one of the most productive greenstone hosted gold districts in the world.
With very few holes ever penetrating deeper than 100 meters on the Munro-Croesus property, the depth potential of the system remains virtually untested. Constantine said these regions will be the focus of a drill program scheduled to begin in late 2010 or early 2011.
New B.C. gold prospect
In May Constantine picked up Trapper Creek, an early-stage gold prospect in the Atlin Mining District of northwestern British Columbia.
Work at Trapper Creek (previously known as the Inlaw property) in the early 1980s by Chevron Minerals of Canada, outlined a large-scale gold-in-soil geochemical anomaly with initial reconnaissance soil sampling followed by 700 grid-controlled soil samples at the 9,280-acre land package. Within the more than 1,000-meter-long anomaly, 13 individual soil samples yielded gold values greater than 1 g/t gold and two sites yielded values greater than 8 g/t gold. A soil sample program carried out in 2008 by Richfield Ventures Corp. validated the earlier findings.
Constantine is gearing up to drill the B.C. gold prospect in 2011.
"The plan at Trapper Lake is to do some additional prospecting, mapping and soil sampling and tee the project up for drilling in 2011. The work will be focused on a gold-in-soils anomaly that is greater than one kilometer long, averages 100 to 200 meters in width and remains open ended along strike," Green told Mining News.
Over his more than 16 years of covering mining and mineral exploration, Shane has become renowned for his ability to report on the sector in a way that is technically sound enough to inform industry insiders while being easy to understand by a wider audience.
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