Guest Contributor | Aug 20, 2019 | 0
Omitiomire Copper Project: from exploration to bankable project
The drilling and sampling programme has revealed that Omitiomire contains substantial copper resources. Craton Mining and Exploration Country Manager, Karl Hartmann told the Economist “The Omitiomire Copper Project has proven to be something with substantial copper resources that will be mined one-day.”
Drilling at Omitiomire started in August 2007 and has been ongoing except during a short time when there was a lack of funding, said Hartmann.
The results of the exploration project so far, has shown that Omitiomire consists of significant copper stratification which merits further exploration. An earlier pre-feasiblity indicated that a mining project can be marginally profitable.
“Subsequent investment in exploration and metallurgical studies increased the resource potential and decreased the projected operational costs, which should increase the profitability” said Hartmann explaining that they have extended their resource from 7.9 million tonnes in 2007 to a respectable 230 million tonnes of copper; on the now 800m wide and 4km long deposit. The initial estimate of the mine’s lifespan was around 13 years but after increasing the resource estimate, the mine’s lifespan could be extended almost indefinitely.
Hartmann said, “This is a low-grade deposit containing an average of 0.53% of copper and if added up amounts to 1.2 million tonnes of copper metal,” which he considers a significant amount according to Namibian standards.
According to Hartmann, the pre-feasibility study has also indicated a more suitable processing technique will help to reduce operation cost.
Using a process called dense medium separation, up to 50% of the hard rock volume, containing no copper, is removed before it gets pulverized in the mill. The mill is the biggest power and water consumer. If less rock is crushed, it automatically reduces cost on electricity and water.
The majority of the Omitiomire resource contains sulphide ore consisting mainly of chalcocite. This mineral is made up of 80% copper and 20% sulphur. “This is a very favourable mineral as it is easy to beneficiate by means of the flotation process.”
Hartmann said that since the pre-feasibility, more tests have been done and they plan to adopt a phased approach to mining the deposit. This includes initial mining near the surface for copper oxide and beneficiation by means of leaching and electro-winning. This will enable Craton to produce copper metal, rather than a concentrate which needs to be exported. “More test work is still in progress to investigate the economic viability of a standalone copper oxide operation.”
He said “with these improvements, we are now in a better position to attract investors as copper prices are fairly good.” Hartmann said that although copper prices play an important role in the investors’ choice, other matters such as lowering capital costs, operational costs, and the tax regime also play a significant part in making the deposit attractive to investors.
“Although much has been discovered to date, there is more potential for copper in the ground. We are continuously re-aligning our schedule as economics conditions and the investor community change; and we need to adapt to that.”
Craton Mining and Exploration holds other EPLs and are conducting more exploration by means of surface sampling, geophysics, geological mapping and drilling. “We have discovered some interesting small copper deposits and work is in progress to determine whether or not more of these can become viable mines.”
Craton Mining and Exploration, as part of their corporate social responsibility programme, have launched the Craton Foundation Trust which aims to assist with educational and social needs.