Site visit: Integra probes new discoveries at historic DeLamar gold-silver property    

After achieving notorious maritime prosperity — initially by salvaging sunken ships — historic entrepreneur Joseph De Lamar became a prominent mine owner in the late 1880s, gaining control of a mountain six miles west of Silver City, Idaho. 

De Lamar sold a majority interest in the property for a pretty profit after rich veins of gold and silver were discovered, before moving on to other mining ventures in Colorado and Utah. 

Today the property, now owned by Integra Resources (TSXV: ITR), is seeing both a revival of the eponymous mine, and is the site of new discoveries. 

The DeLamar project is about an hour’s drive from Boise, and host to the historic mine, was previously owned by Kinross Gold (TSX: K; NYSE: KGC). Integra acquired the project in 2017 with all existing infrastructure in place, including the power grid and water treatment plant. 

With sweeping vista views, the DeLamar project spans about 5,300 acres of patented and unpatented claims, comprising the DeLamar and Florida Mountain deposits, and War Eagle and BlackSheep districts. A further 4,100 acres of leased lands with roughly 1,575 historic drill holes and 145,940 metres of drilling are outlined in historic databases.

The open pit and underground operation lasted for over 100 years, during which time it produced 1.6 million oz. of gold and 100 million oz. of silver until its closure in 1998 due to low metals prices. 

The company produced a preliminary economic assessment in 2019 and prefeasibility study in 2021. The prefeasibility was based on proven and probable reserves of 1.8 million oz. of gold and 92.4 million oz. silver in 123.5 million tonnes averaging 0.45 gram gold per tonne and 23.27 grams silver. The reserve figure includes oxide, mixed, and non-oxide ore.

Integra’s two-stage US$282 million project envisions a larger-scale open pit mining scenario that combines heap leaching and milling to achieve an average production level of 163,000 gold-equivalent oz. per year for the first eight years and a 16-year total mine.

DeLamar and the neighbouring Florida Mountain — a new discovery  —  would have all-in sustaining costs of US$955 per gold-equivalent oz. on a co-product basis, the company said. Black Sheep is another new discovery and a new zone has been identified at Sullivan Gulch. 

De-risking and exploration drilling 

This spring, the Sullivan Gulch exploration results comprised two drill holes, one of which intersected the highest-grade silver intersected to date on the project: 4.1 grams gold per tonne and 446.92 grams silver over 27 metres, including 80.4 grams gold and 14,054 grams silver over 0.4 metre. Also included in the interval are 13.47 grams gold and 1,909.45 grams silver over 5.6 metres, and 40.74 grams gold and 2,839 grams silver over 0.8 metre.

Integra is engaging the local community through its ‘DeLamar Days’ initiative, to familiarize residents and their families on the plan of operations. The latest community event saw over 150 people attend this summer.  The company says were no objections to the project’s draft environmental impact statement from five native surrounding Native American Tribes. 

This week, Integra announced it completed more than 80% of required fieldwork related to the baseline studies for the filing of the mine plan of operations and that it is moving the DeLamar project forward by de-risking through permitting and expanding the resource through further drilling. 

The company has initiated baseline studies that will be fed into the mine plan, which it is planning to file in late 2023 and begun a drill program on the historic low-grade gold-silver stockpiles that were mined and stored by previous operators. The 11,000-metre drill program is aimed at growing the oxide resource to potentially expand future heap leach operations. 

“This material, once successfully defined, could result in a significant amount of low-cost gold-silver mineralized material being added to future mine plans at DeLamar,” says CEO George Salamis. 

Salamis notes that while Kinross was focused on drilling specifically at one deposit, the Integra team discovered the geology ranges at each zone, and this is visible in the drill core in the onsite shack. 

“We now have advanced knowledge of the geology of each deposit as they relate to each other,” Salamis says. “It’s the results of the efforts of the exploration team.”