Question re: sluiced gullies.

[Singer]

Long story shorter:

-Have x70, stock concentric coil plus a 10.5" elliptical DD.
-Live near the VIC goldfields.
-Am highly experienced rock climber.

Having grown up in Utah, spent my adult life in California, I recently moved to Melbourne and just got my first metal detector; I needed something else to do in a land without mountains and have always enjoyed ghost towning. I've been working in the Daylesford area and checking out some spots around there getting to know the land, my detector, and where I like to hang out the most. I've been seeing lots of these heavily eroded sluiced gullies all over the place, more than I've ever seen, actually, and I grew up in mining country. It seems as though obviously there was gold here in the past (for large effort to have been economically feasible) and that we could also assume the sluicers would have missed some of the gold present (when it became economically unfeasible). This is obvious, I know, and being the most urbanized state of the most urbanized country in the world, right is the middle of the "Golden Triangle", I bet a few other people have figured it out and walked these gullies with their detectors and dug up lots of rusty bits and maybe a few pieces of gold kicking around the bottom of the gully. So where does that gold come from? These gullies are 15+ meters deep, obviously not eroded back to the bedrock at the side walls, but often down to the bedrocks (or near) on the bottom. Since we know gold generally settles to bedrock can't we again assume that it would have been deposited concentrated in a V pattern that followed somewhat the contours of the bedrock and in turn the present stream bed? This V pattern would have been the "low hanging fruit" but couldn't there possibly be nuggets up the side walls (outer edges of the V) that would get eroded and drop out over time? Since somebody walking the the bottom can only detect a few feet up the side is there anyone out there who thinks I might have success working the gully side walls off a rope? Also attractive is the notion there wouldn't be any rusty nails or other junk sitting around up there wasting your time.

Any input is highly appreciated.

Singer

 

[nugget71]

Mate let me say this..........from the stories of old prospectors and through my own experiences nuggets can found in the strangest places so yes there could well be some gold in along the side walls but you wouldn't catch me dangling from a rope and harness trying to find gold heheheh I like to have both feet planted to the ground. Good luck!!
Cheers!

 

[nero_design]

The softer soil forming the walls of a gully could indeed hold gold nuggets but I would be more inclined to wave the detector on the walls whilst standing in the gully itself. If the gully wall is high, then you must be very careful because a collapse will be silent and immediate should the wall shift when you dig at it. Some experienced miners warned me of this very concern.

If you're standing in the Gully, you can detect closer to the bedrock with your coil. Over millions of years, gold tends to migrate through softer soils as gravity tugs relentlessly at the heavy metals. You also need to take into account glacial movement which affected Australia thousands of years ago.
These massive mountains of solid ice would push materials along on the ground and shift them kilometers from where they started as the Glaciers melted and formed moving mudpacks (although more likely just meters). If you find bedrock, look for lines cut in it to determine which was the glaciers moved the stones. Up here in NSW, the glaciers have cut lines in elevated sandstone and some lines even hold the original rocks that made them. They sit in small cavities where erosion has caused them to slowly "eat" into the host rock with the markings in it.

If nuggets are to be deposited in the "side walls", you probably need to guess if the area was once a flood plain previously. Your description of a gully which has eroded at considerable depth through soil without exposing much bedrock suggests the zone might have been a flood plain once. In these instances, most of the gold would be below the once muddy deposits so you'll need to be closer to the bedrock. I have found an area here similar to what you have described. I too am probably wasting my time detecting the thicker areas (so far without result) since the X-70 will not detect through to the bottom of the soil. Look for rounded stones which should be deposited lower towards the bedrock to see if this was a floodplain or supported an ancient creekbed. Creekbeds are a MUCH better bet.

Contact your local detector and Prospecting supplier if you need mineral maps. They have one which shows the amount of gold pulled from virtually every region. This will tell you how much (if any) gold has been found there before.

Something else worth considering is that most sluicing operations were abandoned when "new" gold was discovered elsewhere. Then, as the white Anglo-Australians packed up and left, the Chinese prospectors moved in and spend three to six months in the same region. They were not permitted to work in direct competition to the majority of 'white' diggings and would work nearby waiting for the whites to leave. Then they would slowly and systematically peel back all the topsoil in the region (especially near water) and would process all the soil for fine gold and missed nuggets. They would process each dirt pile three times to minimize losses. For this reason, the best places to look are further from water since they Chinese could not really work efficiently without it. Up here in NSW, the Chinese even built massive water courses to get water to other regions (some still stand today). In Victoria, if you think there were sluicing operations in a region, the odds are they were processed very efficiently by the Chinese.

If the gully you have found appears to have been cut more recently via modern water erosion, there may be a good opportunity for you. If I were there, I'd bring a gold pan with me and look for small particles on the lowest soils nearest the bedrock. If any particles are present, you could possibly guess as to how efficiently the area was sluiced and if the gold has migrated far by it's texture. Any sign of small gold may often signify the presence or at least the likelihood of larger nuggets in the region. Fine gold usually has the ability to travel far and appear in gullys having been washed a considerable distance from above. Sadly, fine gold doesn't necessarily mean nuggets either. You need to know that nuggets have been found there by others if you hold high hopes of finding any on your own trips hunting. Some nuggets are formed as 'reef gold' when minerals were squeezed into ducts filled with quartz under volcanic pressure. Some gold forms all by itself in the ground. Fine gold can clump together and fuse into larger nuggets over time and under pressure. Placer gold collected between crevices can also form into nuggets. I sure envy you Victorians with your handy and well stocked gold fields!