Constantine Metal Resources Ltd. ("Constantine" or the "Company") is pleased to report results of metallurgical test work on the Palmer VMS Project, Alaska ("Palmer" or "Project"). Palmer is host to a 4.75 million tonne inferred resource estimate grading 1.84% copper, 4.57% zinc, 0.28 g/t gold and 29 g/t silver* that is open to expansion. Work is being funded by Dowa Metals & Mining Co., Ltd. of Japan ("Dowa"), who can earn a 49% interest in the Project by making expenditures of $22 million over four years.
Highlights of Metallurgical Test Work
The deposit exhibits a very good response to conventional metallurgy. Locked cycle flotation tests yielded smeltable copper and zinc concentrates, with high metal recoveries produced at moderate grind sizes:
- Average copper recovery of 89.6% to a copper concentrate containing 25.5% copper
- Average zinc recovery of 84.9% to a zinc concentrate containing 59.1% zinc
- Combined total silver and gold recovery to copper and zinc concentrates of 89.7% and 75.0% respectively
- Majority of precious metals report to the copper concentrate; 73.7% for silver and 61.5% for gold
Of particular importance to the Project and our partner, who operate the largest zinc smelter in Japan, zinc concentrates produced from the locked cycle tests are of very good quality, with low impurities and no potential penalty or problematic elements.
Garfield MacVeigh, President and CEO of Constantine states: "This is the first flotation test work done on the deposit and we are very pleased with the response to conventional metallurgical processing. In addition to achieving high copper and zinc recoveries, particularly for an initial test program, we are also pleased with the precious metal recoveries. These favorable metallurgical results continue to remove project risk as the Company advances Palmer."
The metallurgical test work program was carried out by SGS Canada in Vancouver under the observation and direction of metallurgists from Dowa. Work was completed on a composite of 212 assay sample rejects from past drilling that is a blend of all major ore-types within the South Wall resource area, with a head grade assay of 1.56% copper, 6.47% zinc, 28.5 g/t silver, 0.19 g/t gold. The program included sample preparation, head sample mineralogical characterization, grind calibration, and a series of batch rougher and cleaner tests under a variety of conditions followed by two locked cycle flotation tests.
The flowsheet for locked cycle tests employed a primary grind k80 at 72 microns. The copper concentrate was reground to a k80 of 26 microns and cleaned three times to produce a final copper concentrate. The zinc rougher concentrate was reground to a k80 of 31 microns and cleaned three times to produce a final zinc concentrate.
About Palmer and the Dowa Agreement
Palmer is a high-grade VMS project located in a very accessible part of coastal southeast Alaska, with road access to the edge of the property and within 60 kilometres of the year-round deep sea port of Haines. Under the terms of an Option and Joint Venture Agreement signed February 2013, Dowa has the option to earn a 49% interest in the Project by making aggregate expenditures of US$22,000,000 over a four year period. Expenditures for each year shall not be less than US$3,000,000. Included in the aggregate expenditure are cash payments to Constantine totalling US$1,250,000 over four years, of which US$500,000 was received upon signing of the agreement. The next cash payment of US$250,000 is due on or before January 31, 2014. Constantine is Operator for work programs carried out during the earn-in period.
Source: http://www.constantinemetals.com/