Idriess was no more than a repeating journalist, with no practical understanding of the theory which he wrote about. A faker, liar. He was caught out many times. The worst of which was re: Simpson and his donkey.
Costean and Trench are two completely differing methods.
Costean's being dug as a part of your loaming, just deeper and longer than a loam hole, and a heavier producer, giving you more of a spread of depth and width to gauge colour run.
Trenches are dug solely for reef examination. Large Trenches become a desperate plunge for sign.
All very informative personal opinions. I will simply continue to follow the definition from WH Ferguson (you may not know of him as he was quite a brilliant observer, diarist and geologist and not taken to slurring the names of people unable to defend themselves - he walked the goldfields of Vic, made the maps, interviewed the surviving diggers etc etc).
"Costean - costeen - A trench cut at right angles to the strike and across the orebody or across the country-rock." But I suppose he is wrong too.
Costean:to dig trenches or small pits through the surface soil or debris to the underlying rock in place for the purpose of exposing the outcrop of a mineral deposit and determining its course
I would have thought that trenching, especially from what I have seen, would be when the shallower mineral bearing material I.e. quartz reef is removed following on from the initial costeaning & sometimes ending in either a tunnel or shaft to continue chasing it deeper.
Probably - there are a lot of definitions and observations. I like to use Ferguson's Victorian goldfield observations when looking at ground. here is one of many of his observations.
"The diggings run for three miles in a north north east fashion as is the case for XXXXXXX. A run of diggings concludes at XXXXXX where little or no work has been carried out. The gold in the area was nuggetty and whilst smaller in size than usual for XXX showed clear indications of sourcing from an exposed reef, XXX chains upslope from the diggings. No indications exist that loaming to the reef has occurred. Mr XXX stated that he saw no need as the reef area was quite exposed. To the south of XXX reef, numerous costean trenches have been dug to strike the lode running XXX chains to the diggings. Further costean trenching in the area would most likely result in further strikes."
Several times now we have found "patches" and the resultant shape of the patch is in a V shape with the point of the "V" at the top of the patch
Subsequent loaming didn't find any trace of fines so couldn't get to the source but we had a very good idea of where it came from
With no indicaters to exactly where the gold oozed from how do we find the source?
Another "patch" we traced nugg's all the way up to a banded ironstone "reef" 20m long but the last nugget was found only a metre away from the reef but no indicators at all with a detector as to where it came from, I havn't loamed this one yet. The closest nugg's were the biggest 5gr
we actually turned rocks over to get the nuggs out of this patch but I would sure like to find the source
What should be my line of attack on these two patches
