The Harvest Home Project lies in the Dunolly area in the Golden Triangle of Central Victoria. GBM is in a Joint Venture with Truelight Pty Ltd on the project.
Since the first discovery of gold at Buggins Flat on the Garabaldi Goldfield in May 1852, Dunolly has been one of Victoria’s most important gold mining districts with both alluvial and quartz reef mining being carried out on a very large scale since the late 1800’s.
The geological and structural settings are broadly comparable to the Ballarat Goldfield. Trending north-northwest through Harvest Home is a broad zone of gold mineralisation some 3.5 km long and up to 0.4 km wide, containing amongst others, the Morans, Harvest Home, Mother O’ Gold and Appletons Gold mines that between them have produced in excess of 60,000 oz (1,860kg) of gold.
The Project lies within a region that has produced a number of extremely large nuggets that include the Welcome Stranger (70.5 kg), the Hand of Faith (27.2 kg) and very recently another large nugget weighing 150 oz (4.8 kg).
The Harvest Home prospect lies within the western margin of the Bendigo-Ballarat zone of the Lachlan Fold Belt that covers much of Victoria and New South Wales. Early Devonian granites intruded the sediments and remobilised the gold in the sediments.
The regional geology of the area is dominated by the Tarnagulla Granite intrusive that is flanked by a zone of contact-metamorphosed Ordovician-aged sediments that in turn are overlain by Castlemaine Group–Lancefieldian sandstone, mudstone, shale and slate of the Bendigo–Ballarat trough.
The primary geological controls are believed to be the fault planes developed along a significant shear zone known as the Goldborough - Whela Shear. The steeply dipping, folded, faulted and cleaved sediments have undergone deformation that was primarily associated with east-west compression. Regionally the beds are steeply dipping and striking north-south or north north-east. The presence of the widespread quartz reefs tends to follow a similar strike. Active shear lines trend to dip steeply west (~ 80o) and are characterised by historically rich, sub-horizontal mineralised veining into the tensional features associated with the hanging wall.
Harvest Home is a shear hosted gold mineralised system that lies at the southern end of the Goldsborough – Wehla Shear Zone, a major deep penetrating structure that has provided fluid pathways for large quantities of gold and quartz. A mineralisation model has been interpreted from 186 drill holes.
There is an Inferred resource of 1,040,000 tonnes at 2.4 g/t with 570,000 tonnes of open pit ore containing 44,000 ounces of gold to a depth of 60 metres.
Ando Minerals N.L. in the 1970’s undertook a significant exploration program along the Queen’s Birthday area with several lines of percussion drilling and indications that at least one diamond drill hole .
Between 1983 and 1989, Bendigo Mining NL/BHP Gold Mines Ltd carried out exploration in the search for reef gold mineralisation. A program of mapping, geochemical sampling, geophysical resistivity traverses and drilling was carried out at South Harvest Home, Harvest Home, Burnt Creek, Mother O’ Gold and South Mother O’ Gold mine sites. Some 185 holes were drilled to a maximum depth of 99 metres.
The majority of the ore defined to date is in a 200m strike length between 9700N and 9900N. The grade within this smaller strike length is higher than the grade for the entire prospect and it contributes to a majority of the estimate of contained gold. There is 60,000 ounces of gold to full depth and 25,000 ounces to 50 metre depth at a grade of 3.55g/t.
|9700-9900N to max depth||614,000t @ 3.04 g/t||for||60,000 ounces|
|9700-9900N to 50m depth||219,300t @ 3.55 g/t||for||25,000 ounces|
GBM Gold is in the final stages of government approvals to mine a 7,500 tonne bulk sample in this area.
Harvest Home deposit 9700N – 9800N
Harvest Home Bulk Sampling Area