White substance?

[->Mikey<-]

Im dissolving some gold cornflake in hcl/bleach slowly but theres this white substance in in the solution. Im wondering if its like a chloride or salt that would slow the dissolving in some way.I havent checked if its soluible in water yet. There is alot of metal for that ammount of liquid but it cant be that concentrated yet because its supposed to get way darker rite?
Man i wish i had nitric to make AR.

 

[Harold_V]

Im dissolving some gold cornflake in hcl/bleach slowly but theres this white substance in in the solution. Im wondering if its like a chloride or salt that would slow the dissolving in some way.I havent checked if its soluible in water yet. There is alot of metal for that ammount of liquid but it cant be that concentrated yet because its supposed to get way darker rite?

If the cornflake you made is from karat yellow gold, what you're doing is making silver chloride as the metal dissolves. Depending on the percentage of silver present, action may cease due to a hard film of silver chloride forming on the surface of the gold. That is assured if the piece is thick enough, but if the items are thin enough, all of the gold will have been dissolved before the layer can fully develop, yielding a solution of gold and base metal chloride, along with silver chloride. It, by the way, is insoluble in acid for the most part, but it can be dissolved with ammonium hydroxide. Do remember that you risk creating an explosive when you introduce ammonia to some solutions.

I agree, your solution should have a much deeper color, so either you have already created an impervious layer of silver chloride, or your solution is lacking in a vital chemical that dissolves the gold. Not being familiar with your process, I hesitate to do any second guessing of what it may be.

Man i wish i had nitric to make AR.

That was my total experience, which likely spoiled me. It was very predictable. I think I can understand your frustration.

Harold

 

[->Mikey<-]

Its not karrat gold. Its about 15g of nuggets i melted together to make cornflake and refine so there shouldnt be "much" silver present. its like a moss that settles quickly. some times i get a white film in my aucl, this may just be more of it. Or a bleach additive i dont know. Im using clorox. None the less i hope i dont loose values if i filter it out in the end.

 

[lazersteve]

The white stuff is most likely salt (sodium chloride) which should dissolve in water. Silver chloride will, as Harold stated, form a crust on the surface of the gold. This crust will darken in color when exposed to light.

The gold in the beaker looks to be pretty thick so HCl-Cl will take some time plus gentle heating to get the job done. A fresh dose of bleach occasionally will keep the reaction going.

Your gold should have been rolled out very thin to get the best results from HCl-Cl. High surface area is the key.

Do you have access to potassium or sodium nitrate? If so you can speed things up quite a bit.

Steve

 

[Harold_V]

Its not karrat gold. Its about 15g of nuggets i melted together to make cornflake and refine so there shouldnt be "much" silver present.

Depends on the source of the nuggets. Gold is typically alloyed with silver in nature, although copper isn't unheard of. If your nuggets run greater than 90% gold, you should have good results following Steve's advice. He had extensive experience with the alternate solutions used for processing. I have none.

i hope i dont loose values if i filter it out in the end.

Unless you toss something, you won't lose the values. Regardless of what the white substance is, if you'll incinerate the waste material after filtration and store it for future processing, and gold that is enclosed will be recovered. If the material is, indeed, silver chloride, you can reduce it and the gold by running the material in a furnace with a good flux. I encourage you to incinerate the waste so you don't have rusting of iron objects in the area. It also reduces the volume so you can store a larger amount in limited space.

Overall, if you can eventually get some nitric, as you alluded, it would really solve a lot of your problems.

Harold

 

[->Mikey<-]

Thanks fer the replys guys but it was just salt like steve said.
Dont know why i didnt add a bit of water before i posted.
sigh.

 

[Harold_V]

Well, it's good that you did! I have no experience with these methods. If nothing else, I learned something that can be of use in the future. It also reaffirmed the idea that I shouldn't make comments in areas where I have no experience.

Harold

 

[cytek]

Mike:

I had this happen to me once before. But what i figured out was i used tap water from my well, which has water softner salt in it. When dissolve gold, i use HCL 8oz with 16 oz of distilled water, then add the clorox till dissolved. Have never seen this problem again using distilled H20.

Cytek

 

[Anonymous]

I always get a lot of salt when using hcl-bleach, I make my own bleach that is much more centcentrated so I do not have enough excess water in solution to hold the salt. Always wondered if gold salt would form crystals but I have never seen any yellow solids, not sure why the solution would staturate for salt buy not gold chloride maybe one of the great chemist on here will answer that for me, I am just a hobbiest (at chemistry) and although I understand quite a bit, I do not know about how the solubility constants interact with different compounds in the same solution.

Jim