After an extended focus on getting its flagship Citronen zinc project production ready in Greenland, ASX-listed Ironbark Zinc is now adding another string to its bow by turning its attention back to the company’s multi-element Captains Flat project in New South Wales.
Together with equal partner, New South Wales Base Metals, a subsidiary of mining giant Glencore, the company has started a helicopter-borne electromagnetic survey over the proven, large-scale Jerangle prospect.
Notably, this marks the first large scale modern geophysical survey over the Captains Flat project area.
The survey is designed to better identify and detail the location, scale and geometry of the identified mineralisation at Jerangle.
Captains Flat is located 45km southeast of Canberra at the southern end of a richly endowed base metals belt of porphyry copper-gold and volcanogenic hosted metal sulphide deposits in the Macquarie Arc. The most famous of these is Newcrest’s Cadia copper-gold discovery in the 1990s.
The project includes the historic Lake George Mine that was first worked between 1882 to 1899 where it produced 26.7 tonnes of silver, 16,100 ounces of gold and 3,841 tonnes of copper from 114,560 tonnes of ore.
It was subsequently reopened in 1937 and produced 4 million tonnes of ore going 10% zinc, 6% lead, 0.7% copper, 1.8 grams per tonne gold and 55g/t silver up to its closure in 1962, making it one of Australia’s largest base metals mines.
The Lake George mine is hosted in a narrow, north-trending suite of volcanic rocks which extend down into Ironbark’s adjacent Peakview Project.
It remains prospective for remnant ore whilst mineralisation remains open at depth with drilling below the mine workings in the 1960s returning up to 1.22m @ 12.4% zinc and 5.4% lead.
Prospects identified to date from historic drilling include Vanderbilt Hill, where a drill hole returned 3.9m @ 10% zinc, 5.3% lead, 0.1% copper, and the Anembo prospect with a historic drill intercept of 3m @ 6.9% zinc, 5.5% lead, 21g/t silver and 2g/t gold.
The Jerangle prospect, that will be the target of the new survey, has historic drill intercepts of 2.25m @ 5.2% copper and 29.4m @ 0.5% copper, 2.2% zinc and 8g/t silver including a 1.9m @ 4.9% copper, 6.3% zinc and 17g/t silver. Ironbark has also conducted its own drilling that returned 4.4m @ 12.05% zinc.
Citronen clearly remains Ironbark’s primary focus, however the start of modern geophysical survey at Captains Flat is a clear sign that the company is keen to develop a second string to its bow with Citronen now at an advanced stage.
