Constellation revolves around Terrazas (April 26, 2004)

Denver-based Constellation Copper (CCU-T) has retained Jacobs Engineering Group to carry out a bankable feasibility study of the Terrazas copper-zinc oxide project in Mexico’s Chihuahua state.

The firm prepared the 2002 prefeasibility study for the open-pit, heap-leach project, with various components of the study awarded to other engineering groups. The study estimated initial capital costs of US$136 million for an operation capable of producing 40 million lbs. copper and 60 million lbs. zinc annually at a projected cash cost of US35 per lb. copper and US25 per lb. zinc. Cathode copper and zinc ingots would be produced using solvent extraction-electrowinning (SX-EW).

The mine life is estimated at 11 years in the prefeasibility, based on resources of 58.3 million tonnes grading 0.35% copper and 0.57% zinc.

The bankable feasibility study will include an updated resource that will incorporate results from 20,000 metres of reverse-circulation and core drilling being carried out this spring. The drill program will also provide core samples for column-leach tests. Meanwhile, bulk samples are being taken from existing underground workings in the centre of the deposit for ongoing metallurgical tests.

The bankable feasibility study is scheduled for completion in 2005, and the company hopes to begin construction by the end of that year.

Constellation Copper (previously known as Summo Minerals) is also advancing its Lisbon Valley copper project in San Juan Cty., Utah. The two projects are expected to make the company one of the lowest-cost copper producers in North America.

Once both mines are in production, Constellation Copper expects to produce 94 million lbs. of cathode copper annually at cash costs averaging US28 per lb., with zinc credits.