The mining newspaper for Alaska and Canada's North
The mining newspaper for Alaska and Canada's North
Mining Explorers 2021 - January 27, 2022
The aurora borealis lights up the night sky above Coeur Mining's Kensington gold mine in Southeast Alaska.
Coeur Mining has decided to delay the restart of mining at Silvertip to investigate the potential of a larger scale operation that leverages the exploration success at this high-grade silver project in Northern British Columbia.
After investing a record US$50.6 million in exploration during 2020, Coeur Mining Inc. set the bar even higher with a roughly US$75 million investment in exploration spending during 2021.
"We expect to complete roughly 1.2 million feet (365,750 meters) of drilling by the end of the year, with the primary objective of further extending mine lives across our portfolio," Coeur Mining Senior Vice President of Exploration Hans Rasmussen said in September.
Roughly US$13 million of Coeur's overall 2021 exploration budget was invested into expanding and upgrading resources at its Kensington gold mine about 45 miles north of Juneau, Alaska.
Building on an infill program completed late in 2020, Coeur began its 2021 program at Kensington by drilling on the Elmira vein located roughly 825 meters east of the Kensington Main deposit, as well as the Johnson vein further to the east.
Highlights from infill and expansion drilling at Elmira include: 4.5 meters averaging 36.3 grams per metric ton gold; six meters of 16.5 g/t gold; and 3.2 meters of 27.8 g/t gold.
Highlights from expansion drilling at Johnson include: 0.4 meters averaging 45.7 g/t gold; 1.3 meters averaging 11.7 g/t gold; and 1.1 meters averaging 24.7 g/t gold.
Coeur said its elevated level of exploration investment at Kensington over the past two years is intended to extend mine life and generate growth opportunities beyond existing reserves and resources.
Building on the late-2020 exploration at Silvertip, Coeur invested roughly US$18 million on resource expansion and upgrade drilling.
Going into 2020, Silvertip hosted 1.8 million tons of proven and probable reserves averaging 8.11 oz/t (14.64 million oz) silver, 8.2% (259.5 million pounds) zinc, and 5.4% (193.2 million lb) lead.
In addition to reserves, the property hosts 2.3 million tons of measured and indicated resources averaging 7.44 oz/t (17.4 million oz) silver, 9.4% (442.1 million lb) zinc, and 4.6% (216.5 million lb) lead; and 1.5 tons of inferred resource averaging 8.3 oz/t (12 million oz) silver, 10.6% (308.7 million lb) zinc, and 5% (143.9 million lb) lead.
Drilling from a drift completed late in 2020 to access 65 Zone quickly led to the discovery of Southern Silver Zone, which represents a new style of vertically oriented and high-grade breccia-type mineralization.
Highlights from early 2021 drilling at Southern Silver include: 6.4 meters averaging 493.7 g/t silver, 23.7% zinc, and 8.7% lead; 6.4 meters averaging 630.9 g/t silver, 14.8% zinc, and 10.5% lead; and 5.8 meters averaging 267.4 g/t silver, 21.3% zinc, and 3.9% lead.
Further surface and underground drilling at Southern Silver discovered a flat-lying "manto" portion of the zone that appears to be thicker in places than the previously drilled vertical breccia zones interpreted as feeder structures.
Highlights from drilling the Southern Silver manto mineralization include: 20.0 meters of 92.5 g/t silver, 16.9% zinc, and 0.5% lead; 10.8 meters of 445.7 g/t silver, 19.4% zinc, and 7.5% lead; and 5.2 meters of 617.1 g/t silver, 7.7% zinc, and 12% lead.
Southern Silver could become a significant source of reserves for Coeur's planned reopening of the Silvertip Mine.
Given the inflationary pressure pushing costs higher and a shortage of available labor, Coeur has decided to delay the restart of Silvertip to investigate the potential of a larger-scale operation that can better leverage the success of the 2021 drilling.
In 2020, Coeur optioned the Tim silver property in southern Yukon from Alianza Minerals Ltd.
Situated just 12 kilometers (7.5 miles) north of Silvertip, Tim is an early staged exploration property with similar high-grade silver-lead-zinc mineralization.
Historical chip sampling from a trench cut across a zone of carbonate replacement mineralization at Tim averaged 352 g/t silver and 9.1% lead across four meters.
Targeting high-grade silver mineralization reminiscent of Silvertip, the 2021 exploration program at Tim included a SkyTEM airborne geophysical survey and surface exploration.
In August, Coeur also entered into an exploration agreement for Millrock Resources Inc.'s Apex gold project about 75 miles southwest of Kensington. This property is home to the historical Apex and El Nido mines, which produced at least 34,000 ounces of gold from ore averaging around one oz of gold per ton during sporadic operations between 1922 and 1940.
Soil sampling carried out during 2021 focused on tracing the mineralized structure and refining vein locations in anticipation of a drill program at Apex this year.
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.
Reader Comments(0)