Marigold Mine Property Boundary

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The Marigold Mine was owned by Glamis Gold Ltd. which was based in Reno, Nevada. Glamis had the majority ownership in the Glamis Marigold Mining Company, with Homestake owning the rest. Barrick purchased Homestake Mining Co. in 2001 in a $2.3 billion stock deal and then Goldcorp purchased Glamis in 2006 with a friendly $9.5-billion deal, and now has a 66.7% interest with Barrick Gold holding the remaining 33 1/3% interest. The mine claim area comprimises 30 square miles of contiguous mineral rights. On April 4, 2014, a deal was finalized in which Barrick and Goldcorp sold their respective interests to Silver Standard Resources Inc. for a consideration of $275 million.

In the 1930's some underground mining was done on the Old Marigold Mine and several thousand tons of ore averaging 0.20 per ton were shipped from the mine. Between 1974-1983 geologist Donald J. Decker staked and acquired claims in the area totalling 4.6 miles, and section 18 was one of them, where the main deposit was. Decker made an agreement with Glamis in October 1986 with his claims in the form of a lease where he earned 5% of gross gold production from the Decker claims only. The discovery of high grade mineralization which led to the current workings in section 18 took place in 1985 and 1986.

Development of the mine started in August 1988 and was based on the 8 South deposit which was in section 8, and mining started in 1989. The initial reserve estimate was 367,000 ounces with a grade of 0.073 per ton, with a resource of 5.028 million tons. Glamis was a pioneer in the heap leach method of gold extraction so recovery was expected to be 90%, and this made for an estimated mine life of 5 years. The total capital cost to develop the mine was $37 million.

Marigold is located on the prolific Battle Mountain Gold Trend which is around 100 miles long and 20 miles wide in a southeast to northwest direction. The gold is a Carlin type deposit where the particles are dispersed in coarse and fine grained sedimentary rocks. Carlin type gold is rarely visible to the human eye even in high grade samples and the grains are microscopic in size. The gold was emplaced in the rock by hot water solutions related to volcanic activity which occured millions of years ago.

The mine itself is a standard truck and loader operation and the main pit on section 18 is designed to be 800 feet deep. The ore is crushed and milled in ball and rod mills which grind the rock to expose the gold particles. The gold is stacked in leach pads then sodium cyanide is used to dissolve the gold particles, and the gold laden cyanide is recovered in columns onto activated carbon. The average heap leach recovery is around 70% and the facility can handle 2.5 million tons of ore per year. Through the leaching process most of the gold is recovered in a few months and the mine operating permit allows for the stacking of the leach pads to be 180 feet high if needed.

In 2000 Glamis announced it had made a new discovery from 172 drill holes and based on the 90,000 feet recovered came up with a measured and inferred resource of 1,453,600 ounces. This was called the Millenium project and was projected to extend the life of the mine by 8 years. This project mined the newly discovered Terry deposit, and the deposits on section 30 and 31.

Recent exploration activity has discovered the mega ore body between the original ones on section 18 and the 31 North and South deposits which will be mined and will create a contiguous pit which will be around 3 miles long. This will increase the mine life by an estimated 11 years. The feasibility for this project study represents an entirely new life-of-mine planfor Marigold, incorporating the existing Marigold operations, as well as the Millennium Project that includes the Terry Zone and the Section 31 and Section 30 orebodies to the south.

Reference:

www.infomine.com/minesite/minesite.asp?site=marigold

mineralsappraisers.com/ellis%20gold%20appraisals.pdf

www.goldcorp.com/English/Unrivalled-Assets/Mines-and-Pr...

www.barrick.com/GlobalOperations/NorthAmerica/MarigoldJ...

www.nbmg.unr.edu/dox/mm/mm06.pdf

www.fundinguniverse.com/company-histories/glamis-gold-l...

www.dmec.ca/ex07-dvd/Decennial%20Proceedings/Expl97/05_...

cnrp.ccnmatthews.com/news/releases/show.jsp?action=show...

cnrp.ccnmatthews.com/news/releases/show.jsp?action=show...