Woodline alluvial gold area, Bulong Goldfield, Kalgoorlie-Boulder Shire, Western Australia, Australiai

Regional Level Types
Woodline alluvial gold area	Area
Bulong Goldfield	Ore Field
Kalgoorlie-Boulder Shire	Shire
Western Australia	State
Australia	Country

Gold was discovered here in 1904, when a worker laying a tramline from Kanowna, un-earthed a 3 ounce nugget. A rush ensued and soon 800 men were working the patch. Shortly after a new smaller patch was found to the west. Nuggets up to 100 ounces were found.

Years later in 1912, government geologist C.S. Honman studied the site and produced a detailed report. The site is on a salt-bush flat flanked to the west and east by ironstone ridges. The largest nuggets were found around the roots of an old tree just above the western edge of the flat. After the alluvial miners left, various prospectors sank shafts to 30-50 feet seeking the source of the alluvial gold, but found little. When Honman visited, the site was deserted. He states J.J. Joyce was the last prospector to that point.

The site is on the old woodline tramline from Kanowna, possibly now an old track heading directly west from just north of the modern nickel mine, and bordering the north side of this track. Honman states it is 2.5 miles south of P.A. 1005Y, and 6 miles north of Bulong.

The western ridge strikes north-east, and the eastern ridge north north-west. They converge to the south but it is indistinct. The bedrock is covered by a thin layer of alluvium, under this decomposed fine grained greenstone, quartz carbonate rocks, schist and laterite.

The main patch totalled 18 acres, the best gold found in a crescent shaped area extending from the tramline to the western ridge, with the convex side facing south.

Honman then attempts to determine how the gold arrived at the site, although no primary source had been uncovered to that time. He states there were two movements. The first formed a series of parallel and vertical shear planes and faults. This was caused by the intrusion of the coarse grained quartz carbonate rock into the greenstone. The fault planes show banding, with pockets of pug and fragmental rock at intervals, with an irregular strike and dip. Only narrow quartz veins formed to 4 inches wide. The walls of the vertical seams show banding, with ironstone pseudomorph aggregates.

The second movement resulted in a series of flat lying fissures in fine grained rocks, and the quartz-carbonate rock, resulting in cross vertical seams. This faulted them in places, with the fissures filled with clear glassy quartz containing schorl.

The vertical seams are associated with secondary re-crystallisation of pyrite, resulting from the intrusion of the tourmaline bearing veins. Gold was brought to the surface by mineral solutions, then released from the pyrite as free gold by metamorphic actions, leaving it free in sugary quartz.

The smaller patch to the west is found near the top of the western ridge, and trends north. Only fine gold was found here.

Cyprus Gold explored the site across 1996 to 2000, discovering a prominent gold anomaly. They state gold is found at the contact of basalt, and altered ultramafic rocks, as a supergene enriched zone between the two rock units, where the weathering is deeper.

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