Gold Indicators and Indications (Part 2)
Well, I gave the gold indicator versus gold indication thing my best shot in the previous post so I'll let that sleeping dog lie down for now. Moving forward, I want to bring your attention to what Aussie fossicker and miner Jack has to say about all this (and especially the importance of sampling). Most of us can relate to what he's saying here, so let's get started.
"In a new area tracing indicators is not that hard and the best way to do this is by pan. First you should ascertain if there is gold located within the area you wish to prospect. You can get this information from preliminary research about the area. Now using a gold pan, check all the recommended places first: behind rocks, around logs and tree roots, and any area you can see that forms a little low pressure eddy when the river is in flood. Even though there may be no gold in the pan, take note of what is left in the bottom of it. Do this for each pan and after a few pans a pattern should start to appear. One or more types of the same material should be repeating itself in each pan. This is one way to determine the indicators for the area you are working."
"The Best Sign"
An indicator can be anything. It could be a high concentration of ironstone or lots of black sands, or any one of the many rocks associated with gold in your area. But as the name implies, it is only an indicator and will not necessarily put you on the gold. But indicators are the best sign you have to work with and 90% of the time they will put you on the gold, including the best gold. That's why you want to look for those indicators. Once you start sampling an area that has good gold, you must continue test panning in every direction...up, down, left and right of the hole in which you are working. If you want to stay on the gold you must do this. A small lead can twist and turn in a matter of feet and this is the only way you can keep on it."
"How Do I Find My Indicators?"
"Up to now I have always done my gold panning and sluicing where there was known gold, taking a sort of 'pot luck' approach. But these days I want to find my own spots...away from the the maddening crowd, so to speak. I have read here and there about searching for indicators but I don't really follow those interpretations. A bloke I spoke to once said that quartz and ironstone together was an indicator for gold where I'm currently looking, but the fact of the matter is that there is quartz and ironstone every bloody where! And if I pan some dirt I get nothing. In the area I work there are also lots of rocks laying around that are a mix of ironstone and quartz and sometimes what look like 'melted' bits in it. Are these what I am looking for or should I be looking for areas where there are heaps of smaller pieces? There is also a lot of granite in the area, but not in the old wash I am concentrating on. It's a sad fact that I have read heaps of books but nothing really describes exactly what to look for in this regard."
("Salt and pepper" ground in an Australian gold area. The 'salt' is the quartz and the 'pepper' the ironstone that Jack speaks of.)
"Every Location is Different"
"Well every location is different...different rocks and different material associated with the gold occurrence of a particular area. Some areas have heaps of ironstone and iron sand while others have bugger all! Some areas have heaps of quartz and some don't. The indicators are the stones and rocks familiar to a specific or known gold field or area of gold occurrence. Generally speaking, what you're looking for is a more concentrated 'line' of associated material. This material is usually heavier than the other 'normal' rocks, stones, or material that make up the disintegrated and eroded country rock of a particular area. This indicator material will be the associated material that has come up from down below with or was carrying the gold. Do you know what the typical specimen stone is of the particular area you're interested in? Ironstone is a good indicator here as gold is associated with it in gold specimens. Ironstone is quite heavy and like heavy sands will be deposited during times of high flood or significant water flow along the 'gold path' in a creek, river, stream, or wash."
"Yes, it's a sure thing there will be a crap load of ironstone and quartz scattered all over the place, but what you are looking for is a general line of concentration of this material or its heavier elements in a particular part of a known gold field. Often you will have to sample from stream bank to stream bank and note what is in every sample pan. Mark those spots where you get greater concentrations of heavier materials with an upright stick, pile of small rocks, etc. Even oxidized iron junk such as nuts, bolts, and nails count as these are heavy elements that are often associated with gold deposition. These items will also be heavier than the general stones of the area."
(Old, oxidized iron junk can be a great indicator of gold.)
"Marking the Spots"
"Usually, you'll want count the specks of gold you find and mark where the greatest number are. Do this up and down stream say every meter (three feet) apart, for example. The more times you do this up and down the stream the better the picture you will get of the 'gold line' in the stream. Let's say you do a sample dig from bank to bank and you find a spot that's better than all the rest along that line across the streambed. That will be your starting point on the 'gold path.' Go upstream from that point one meter and take test pans to the left and right until you pick up the best spot again. Mark that spot and then move up another meter and do the same thing. Do this both upstream and downstream. After you do this, step back and look at where you have been putting your marks. You will see a definite 'path' where the better areas are. This is the 'gold path' and where you want to dig...moving up from mark to mark. Then clean out the best area of the run of gold (where the gold is most concentrated). Gold is your best indication, but at a glance the associated rocks with the gold are a good place to start as far as indicators go."
"Mainly 'Shotty' Gold"
"Where I fossick, the creeks produce quite a useful indicator...lots of lead shot from the early days. I usually poke around with my hand suction pump first, looking to see what's around the place and when I start finding lead shot the gold is usually there too. These creeks I'm talking about have well and truly been worked over from the very start and tend to be patchy. But each time I use the hand pump it doesn't take very long to find shot and gold 'clinkers.' There's not much fine or flour gold evident in this area. The gold is mainly 'shotty' with the occasional mini-specimen with quartz or ironstone attached, which is very interesting and requires future attention. On occasion it's not unusual for me to get 10 or 20 plus bits of shot in a pan this way. And looking at the level of oxidation it's probably been there for a long time...undisturbed. My 'pard' and I do our environmental good deed and take the lead home with us. Maybe we should go in to the scrap lead business! And, as always, it's important to take care not to foul the area up after sampling with tailings from either pump or pan."
"I hope this was of some help. I know it sounds time consuming to do all this sampling. And it is. But once done you are on a winning streak as you WILL know where the best run of gold is and you'll clean up the best of it without wasting time by blind stabbing and moving shed loads of useless material for nothing and no gold."
I couldn't have put it better. My thanks to Jack for this input.
There's more to come...
(c) Jim Rocha 2018
Questions? E-mail me at firstname.lastname@example.org