JOHANNESBURG (miningweekly.com) – The demonstrably successful new AngloGold Ashanti gold-mining technology has produced 40 kg of gold from ore with enormously valuable gold grades of more than 200 g of gold for every ton mined.
The South African Technology, as it has been called, has so far mined only in no-go areas, which have been bypassed for conventional mining on the grounds of being excessively hazardous.
Revealing this after presenting a magnificent set of results with every metric excelling with the exception of the lagging gold price, AngloGold Ashanti CEO Srinivasan (Venkat) Venkatakrishnan told Mining Weekly Online that the company was now rolling out the technology on five sites using locally produced raise-boring equipment (also see attached video).
“We continue to invest in the South African technology piece,” he said, describing it as the “single key we have to improve productivity, which is the answer to a number of issues within the South African mining industry”.
The key breakthroughs the company has achieved as it completes its eighteenth drill hole at Tau Tona gold mine are slashed drilling times, backfill technology beyond the trial stage and a drilling mechanism that crushes the core to paste for easier processing.
Drilling times that used to take 30 days are now taking 3.5 days, with 2 days the new target.
“The new machines we are manufacturing are doing a very good job,” Venkat told Mining Weekly Online, adding that a significant breakthrough had been achieved with adjacent drilling.
A second production site is being built at Tau Tona, with other sites going up at Kopanang, Great Noligwa and Moab Khotsong.
The machines are being made to drill even the narrowest of reefs and can also be used in hard-rock, narrow-reef platinum mines.
AngloGold executive VP South Africa region Mike O’Hare said the new reamer being used in the potentially “game-changing” mechanisation drive was enabling the company to complete a hole far faster.
All the ore has been extracted from adjacent holes – “skin-to skin” – with negligible deviation.
“We plan to ramp this up quite significantly over the year,” O’Hare said.
The average grade in the holes drilled is an enormous 90 g/t, with one hole coming back at more than 200 g/t.
“Just in the research and development phase, we’ve managed to mine over 40 kg of gold and we want to quadruple that number in 2014,” he added.
AngloGold Ashanti reported low all-in sustaining costs in 2013 and a yearly production that rose for the first time in almost a decade after it successfully cut spending and commissioned two new mines.
The JSE- and NYSE-listed gold company took yearly output to 4.105-million ounces at an all-in sustaining cost of $1 015/oz.
Despite free cash outflow reducing from $205-million to $82-million, after all capital, tax and interest payments, the AngloGold board decided against a dividend declaration.
“It would not be a smart move at this time to borrow money from the banks to pay dividends,” the AngloGold CEO commented to Mining Weekly Online.
The new Tropicana mine, in Australia and Kibali mine, in the Democratic Republic of Congo added 106 000 oz to the AngloGold total at a low average cash cost of $532/oz.
Sold off is the small Navachab mine, in Namibia, and closed is the under-performing Yatela mine, in Mali.
The current worst-performing mine, Obuasi, in Ghana, is undergoing reform, which will include an element of mechanisation.
Projected 2014 production is expected to be from 4.2-million ounces to 4.5-million ounces.
The capital expenditure outlook for 2014 is a decline of 31% to between $1.3-billion and $1.45-billion.
In 2013, strong quarter-four (Q4) production of 1 229 000 oz rose 43% on Q4 2012 and 18% on the previous quarter.
Net debt to earnings before interest tax depreciation and amortisation fell to 1.86 times, down from 2.02 times in Q3.
Adjusted headline earnings leapt 49% to $164-million and the all-injury frequency rate was the lowest ever at 7.33 for every million hours worked for the year.
Corporate and exploration costs fell 20% in Q4 from the previous quarter.