LeighB

Hi all I'm seeking input from the experts to answer an archaeological question about ancient gold recovery. As a geologist, I know the questions I'm asking don't have specific answers but I would value your collective experiences. I'm looking at a situation where gold is recovered from ephemeral streams and where mostly it will be the result of flash floods (and of course before metal detectors made life a bit easier). For those who have worked in these environments, I know the gold distribution can be a lot less predictable than in regular streams. My first question is how effectively gold is separated towards bedrock in such a setting. Can one strip off less prospective sediment and focus on specific bands the way one might in other settings? Secondly, what proportion of the gold will be in particulate form (fine flour and discrete nuggets) versus within composite cobbles with quartz and iron etc (I know primary geology will be a factor here, so assume the sources are numerous quartz veins with gold and associated sulphides). Last, whether anyone has found by detecting a quartz cobble or fragment in a defined stream bed (i.e. not at the base of slope or in gullies) containing gold that is not visible from the outside, and how rare this might be. Any thoughts, observations or questions for clarification will be most welcome. Thanks in advance for your time.