ysebag,
Gold will not dissolve in HCL, but oxidized gold will form a gold salt with HCl (AuCl3).
Nitric acid will not dissolve gold, but it can Oxidize the gold, (probably forming a passivated layer of oxidized gold just a guess here).
When we add an oxidizer to the hydrochloric acid HCl, the oxidizer oxidizes the gold so that the HCl will form AuCl3 in solution.
Nitric acid is only one strong oxidizer that is strong enough to oxidize gold, household bleach like you wash clothes in to get them white (sodium hypochlorite) is another, the bleach form chlorine gas in solution when mixed in acids, it is this chlorine gas that oxidizes the gold.
Once gold is in solution (dissolved)we no longer need the oxidizer, in fact the oxidizer now will not let us get our gold back out of solution.
Oxidized means the atom has a loss of electrons, reduced means to gain of electrons.
When a gold atom lost its electron it is dissolved into solution, to get the gold back out of solution we must give it back all of its electrons so that it will fall out of solutions as many gold atoms (metal gold powder), as long as there is an oxidizer in solution like nitric acid we cannot give back the gold its electrons and make it into gold powder, because the nitric acid in solution keeps on taking the electrons away from the gold, so as long as there is an oxidizer like nitric acid or chlorine in solution we cannot reduce (give back electrons) our gold back to metal.
When dissolving gold several things can help to make things work better for when you are later trying to get your gold back out of solution.
Do not dissolve gold with base metals.
Keep tin out of solution with gold.
Use only the minimum amount of oxidizer needed to get the gold dissolved (using heat to help) and to also insure all of the oxidizer has reacted before adding more.
ysebag,
I can answer a few questions, but from reading what you have said, there is no way I can answer all of your questions, You have a lot to learn, I can help some, but for you to learn what you will need to know to be successful in this field you will need to study, You are very lucky it is all here on the forum, many have answered these many times, so just keep reading and soon you will find many answers, you will find answers to questions you did not even think of, you will also find many ideas of how to do things and what to look for when trying to find scrap, or very useful tools to make the work easier.
If all I did was answer your question I would cheat you out of finding many treasures (these treasures you will find in this forum).
Have you read the guide to the forum?
Have you visited Laser Steve’s web site?
Have you been studying HOKE’s book?
Have you studied the Forum?
If not you are missing the real treasure, it is not in that gold solution you have there now (that is only a tiny bit of value that you may not get if you do not understand how), the real treasure is found by studying and getting wisdom of how to recover and refine, this wisdom you will not get from someone answering a couple of questions, this understanding comes from hard work studying and practicing what you will learn.
And this forum has the goldmine of information just waiting for you to go in and get the treasure.
ysebag, all of the answers are there.
