TORONTO (miningweekly.com) – Curis Resources, the TSX-listed junior hoping to build an in-situ copper mine in Arizona, is considering selling a minority stake in its Florence project to a strategic investor, CEO Michael McPhie said on Tuesday.
Speaking in an interview, he said the company had already signed more than a dozen confidentiality agreements with companies interested in funding the estimated $238-million copper project.
“By the end of the year, we will have a clearly defined path on the project’s funding,” McPhie said, adding that Curis had received “a lot of interest” from banks and institutional investors in financing.
The Florence project is located about 120 km south-east of Phoenix, and has a 429-million-ton measured and indicated copper oxide resource.
The company plans on extracting the metal using in-situ leaching, a process whereby it pumps a weak acid into the orebody through wells, which dissolves the copper, to be pumped back up to surface where Curis will treat the solution at a solvent-extraction electro-winning (SX-EW) plant to produce copper cathode.
This production method, more common in the uranium sector, allows for capital costs less than one-third of a similar size openpit mine, and also places operating costs in the lowest quartile, McPhie said.
There are currently no copper mines that solely rely on in-situ leaching production, though Glencore’s Mopani mine in Zambia does use the technique for some of its output.
There have also been past producing in-situ leaching copper mines in the US.
Curis is busy completing a feasibility study for the project, which is due by the end of the year, with permitting to follow shortly after.
The firm announced on Tuesday that the Arizona State Land Commission had sent it a letter of support for Florence’s development at the end of August.
The company aims to build a first-phase pilot operation next year that will produce one- to two-million pounds of copper yearly, which will allow it to make sure the circuit in the SX-EW plant is optimised, thereby shortening the commissioning time for the second phase.
Once commissioned, around the second quarter of 2014, Florence will ramp up to commercial production averaging around 76-million pounds yearly (35 000 t/y).
McPhie stressed that bringing in a strategic partner was just one of the funding options Curis was considering, but pointed to a deal last year where Canada’s Taseko Mines sold a 25% stake in its Gibraltar copper mine to a Japanese consortium led by Japanese trader Sojitz as being a favourable model.
Shares in Curis, which is backed by Vancouver's Hunter Dickinson climbed 3.7% on Thursday to trade at C$1.95 by 11:09, on thin volumes.
BHP Billiton aquired Florence, originally discovered by Conoco Phillips in the mid-1990s, but dropped the project after commodity prices went through a rough patch later that decade, selling it to a US real estate trust in 2001.
Before BHP sold it, the diversified giant built a pilot plant and conducted a feasiblity study, meaning that much of Curis' work has already been done. The junior bought the asset in 2009, and listed on the TSX-V the following year, graduating to the main board in 2011.