DiamondCorp (LON:DCP) says it can now speed up the underground development of the Lace diamond mine in South Africa.
The company’s 74%-owned mine continues to ramp up underground development close to schedule and within budget.
It has completed 11% of the tunnel development; it had aimed to finish 12% of it by this point, but DiamondCorp says it has been limited to two crews operating three shifts while blasting the temporary vent raise which by-passes the blockage in the vertical shaft.
Now this has been completed, and following the installation of surface exhaust fans this week, multi-blast conditions now exist underground and the rate of development can increase to more than double the current rate of 200 metres per month.
The last of the dump trucks and underground loaders are currently being assembled and will be commissioned by the end of the year, helping reach the maximum development rates.
The new box-cut is completed and the twin declines have started from the base of the ramp, while the underground conveyor belt system is on schedule with installation of the first leg about to commence.
Tailings re-treatment has been optimised to maximise dump treatment rates, diamond output and cut operating costs. The first sale of diamonds from tailings will now take place after the Indian Diwali festival in November.
A diamond beneficiation joint venture deal has been signed with Distinctive Choice, a small Johannesburg cutting and polishing factory, specialising in the manufacturing of large, high quality diamonds.
This means DiamondCorp has the option to process some of the larger, high quality diamonds which fall outside the off-take agreement with Tiffany.
The first stone under the joint venture (JV) was an 8.36 carat white diamond with a reserve price of US$3,100 a carat. Three diamonds were cut from this, the largest of which was sold for US$68,000.
Its share of the sale meant a return of 185% for DiamondCorp.
“Over the life of the mine, the beneficiation joint venture has the potential to provide LDM [Lace Diamond Mines] with significant additional income, give important insight into how the Lace diamonds perform during polishing and assist with beneficiation targets under the Mining Charter,” it said.
Drilling of the Bulge area continues, DiamondCorp added.
The shares rose 1.9% to 6.75p.