A
Anonymous
Guest
Hi, I'm totally new to this stuff. I have an area on my property that is very geologically interesting and has all the precursors for gold formation. The ore is lightly variant but very mineralized, there are several quartz based gossans as well within the very immediate vicinity. I've also found a very large vein of what appears to be chlorite, layered with quarzite and pyrite immediately bordering one of the gossans. There is very very abundant pyrite within all of the surrounding ore as well. I also am under the firm belief that there is tellurium involved here. I've been taking different samples and doing the following with them:
-Crushing the samples down to a mineral flour sized particle (-300 mesh) to increase the surface area for dissolution of any gold
-Putting a small amount of the powdered sample into a small test tube and filling the test tube half way with Aqua Regia made with hydrochloric acid and nitric acid
-in an attempt to dissolve any gold that may be present, I leave this overnight in a room temperature environment and shake it periodically to stop the powder from caking on the bottom of the tube
-about 12 hours later, I take a sample of the solution from the top of the the mixture (to try not to get any particulate in the drops I use for testing)
-I then place 2-3 drops of this sample into a glass petri dish
-I test it by dropping 1-2 drops of the shor international Precious Metal Detection Liquid into it and I look for color changes as indicated on the bottle. I am guessing this is stannic chloride? You can see this product at the bottom of this page: http://www.shorinternational.com/RefinAcidinstr.htm
-In the samples that I would most likely suspect a gold content, I seem to be getting a very dark black color appearing instantly with this test. Many samples are also varying shades of black, and some are void of any color change.
My real question is whether this is anywhere near a valid method to test for the presence of gold. I'm sort of hoping that Harold will chime in on this one as well because he seems unbelievably knowledgeable and I read a posting by him talking about getting a black color from samples where tellurides were involved. I tested the method extremely generally by placing a tiny piece of shaved 18k gold into a blank solution of the aqua regia and did the test as usual. I got an instant jet black result from this. As well, is there any way to understand what type of concentration may likely exist in my different ore samples aside from sending these to a lab for something like a fire assay?
Sorry in advance if any of these questions are ridiculous. I guess we all have to start somewhere. :lol:
THANKS!
-Crushing the samples down to a mineral flour sized particle (-300 mesh) to increase the surface area for dissolution of any gold
-Putting a small amount of the powdered sample into a small test tube and filling the test tube half way with Aqua Regia made with hydrochloric acid and nitric acid
-in an attempt to dissolve any gold that may be present, I leave this overnight in a room temperature environment and shake it periodically to stop the powder from caking on the bottom of the tube
-about 12 hours later, I take a sample of the solution from the top of the the mixture (to try not to get any particulate in the drops I use for testing)
-I then place 2-3 drops of this sample into a glass petri dish
-I test it by dropping 1-2 drops of the shor international Precious Metal Detection Liquid into it and I look for color changes as indicated on the bottle. I am guessing this is stannic chloride? You can see this product at the bottom of this page: http://www.shorinternational.com/RefinAcidinstr.htm
-In the samples that I would most likely suspect a gold content, I seem to be getting a very dark black color appearing instantly with this test. Many samples are also varying shades of black, and some are void of any color change.
My real question is whether this is anywhere near a valid method to test for the presence of gold. I'm sort of hoping that Harold will chime in on this one as well because he seems unbelievably knowledgeable and I read a posting by him talking about getting a black color from samples where tellurides were involved. I tested the method extremely generally by placing a tiny piece of shaved 18k gold into a blank solution of the aqua regia and did the test as usual. I got an instant jet black result from this. As well, is there any way to understand what type of concentration may likely exist in my different ore samples aside from sending these to a lab for something like a fire assay?
Sorry in advance if any of these questions are ridiculous. I guess we all have to start somewhere. :lol:
THANKS!