Kaolinite?

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Doing a bit of loader work on one of our leases. Hit this stuff again. Its white inside and iron stained on the outside. Breaks easily. One smack with pick and the rocks break. Inside is white and if you look closely there may be small clasts or fragments of other rocks in it. I am thinking Kaolinite??? More importantly, do nuggets go below this layer??:)
white rocks.jpg
 
They can, but if that is quartz I can see as well it is probably kaolinized granite (in which case probably no deeper nuggets)
 
Granite being the effective bedrock, maybe your only chance would be to look for variations in level that would have been an ancient surface and check for deeper spots ie cracks and crevices into which gold may have deposited.
 
Can confirm at one metre down, no signs of life :(
Nice rocks though...pity none of them are a gold colour :)
The bedrock is mapped as metamonzogranite, but we are very close to the contact zone with the greenstones....might have to move a bit further west....Have found many many bits on this spot, now I know nothing at depth....
Plan now would be to move west closer to the contact zone and around the exposed quartz blows.
.......Or start kaolin mine ha ha
 
Sounds like a good plan. My understanding is that gold is deposited from hydrothermal fluids emanating from magma chambers into neighbouring or overlying rocks. This process effectively depletes the granitic magma chamber of its gold.
if overlying rocks are eroded away their gold can then sit on top of the granite or perhaps be moved there by eons of weathering processes in adjoining (contacting) rocks.
In Victoria this has been known at Rheola where a rich field of nuggets was found in alluvium overlying a granite bedrock. Nothing was found in the granite underneath and it was assumed that the nuggets were derived from reefs in overlying Ordovician rocks long ago eroded away.
To the side of the granite surviving Ordovician rocks were found to contain rich nuggetty reefs and associated rich runs of diggings.
 
Sounds like a good plan. My understanding is that gold is deposited from hydrothermal fluids emanating from magma chambers into neighbouring or overlying rocks. This process effectively depletes the granitic magma chamber of its gold.
if overlying rocks are eroded away their gold can then sit on top of the granite or perhaps be moved there by eons of weathering processes in adjoining (contacting) rocks.
In Victoria this has been known at Rheola where a rich field of nuggets was found in alluvium overlying a granite bedrock. Nothing was found in the granite underneath and it was assumed that the nuggets were derived from reefs in overlying Ordovician rocks long ago eroded away.
To the side of the granite surviving Ordovician rocks were found to contain rich nuggetty reefs and associated rich runs of diggings.
Hi Hawkear - what you say is correct for many goldfields overseas and some in eastern Australia, but it is often incorrectly extrapolated to places like Victoria and the eastern goldfields where little gold has any clear association with granite (possibly none at all). The granite at Rheola is probably unrelated to supplying the gold and is younger than it (the primary gold, not the younger alluvial gold). Not disagreeing with what you say, except that granites that do supply gold elsewhere are not strictly depleted by the process - commonly the gold is within the granite (Cadia NSW would be an example).

Rheola is a little tricky as a diorite intrusion behind the church possibly pre-dates the gold - but I doubt if it has anything to do with the gold.
 

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