suspect precipitate

[Geo]

i was presented the chance to refine approximately 1 OZT of 10k jewelry. the individual wanted a refined piece of gold to keep. i agreed letting them know that i dont have a lot of experience with karat gold. i didnt have enough silver to inquart so that was out. i ran out of nitric a couple of days ago, so i couldnt use nitric without making a fresh batch. ok, heres my problem. i used AR to dissolve the 10k completely. the solution was a deep green. after cooling, a fair amount of AgCl precipitated. i filtered and let it settle and filtered again. the solution was crystal clear. i dropped with SMB. here's the problem. more powder dropped than should have. there was the tan powder and then there was a lighter, pink, colored precipitate mixed in. i boiled in hcl and then rinsed. boiled in water and then rinsed. boiled in ammonium hydroxide and then rinsed. boiled in water again and then rinsed and decided to dissolve in hcl/Cl just to be sure. after adding twice the amount it should have taken, the pink precipitate is still there. the tan powder is in solution but this pink stuff is just sitting on the bottom. does anyone know what this could be and besides the obvious things ive already pointed out, what could i have done wrong if indeed i did anything wrong.

 

[NobleMetalWorks]

i was presented the chance to refine approximately 1 OZT of 10k jewelry. the individual wanted a refined piece of gold to keep. i agreed letting them know that i dont have a lot of experience with karat gold. i didnt have enough silver to inquart so that was out. i ran out of nitric a couple of days ago, so i couldnt use nitric without making a fresh batch. ok, heres my problem. i used AR to dissolve the 10k completely. the solution was a deep green. after cooling, a fair amount of AgCl precipitated. i filtered and let it settle and filtered again. the solution was crystal clear. i dropped with SMB. here's the problem. more powder dropped than should have. there was the tan powder and then there was a lighter, pink, colored precipitate mixed in. i boiled in hcl and then rinsed. boiled in water and then rinsed. boiled in ammonium hydroxide and then rinsed. boiled in water again and then rinsed and decided to dissolve in hcl/Cl just to be sure. after adding twice the amount it should have taken, the pink precipitate is still there. the tan powder is in solution but this pink stuff is just sitting on the bottom. does anyone know what this could be and besides the obvious things ive already pointed out, what could i have done wrong if indeed i did anything wrong.

Could your pink precipitant be Manganese?

If it is, you should be able to dissolve it with HCl and heat, then filter out your brown precipitant. To drop the Manganese you would then add Sodium Hydroxide + Bromine and water, then heat, which should give you a pink precipitant that you can then roast, it should turn dark black or brown. You can get Bromine at most pool supply places.

Manganese is sometimes used in white gold, and can, from what I understand, be used with other metals to strengthen karat gold.

If your pink precipitant is Manganese, I have no clue what form it precipitated as, hopefully someone far more knowledgeable will come along and correct me if I am wrong. As with other metals that we precipitate, they tend to be more voluminous than not, but you already know this and far better than I. I have been making a lot of silver nitrate to use in making silver nano spheres, and I notice a 1/5 increase in the weight after I dry it out. So if I put 5 ounces of silver in, I get 6 ounces of silver nitrate out.

Scott

 

[NobleMetalWorks]

I forgot to mention:

Manganese or Magnetite will give you a green chloride, that might be the green color you experienced with you dissolved in AR.

Scott

 

[Geo]

i gave it a good boil in hcl first. thats the first thing i did after rinsing from the SMB drop.the gold dissolved with no problem. i placed the solution and the powder in a graduated cylinder so i could decant without disturbing the powder. i filtered through 3 wet coffee filters so the resulting solution is nice and clear. i will let it sit undisturbed until tomorrow to make sure i got all the powder out. i have the powder in a glass pyrex cup full of water so it doesnt dry. ill take a picture in the sunlight and post it. someone with better knowledge than me will have to explain what dropped with the gold but will not dissolve with the gold. after dissolving the tan powder out of it, its a little darker red than pink now.

 

[NobleMetalWorks]

Geo,

I was a little hesitant to post what I did, you know far more about this stuff than I do. But when you mentioned the green solution and the pink precipitant, it rang a bell. I'm going to be following this thread, just because I'm really curious what you precipitated out.

Good stuff, I like mysteries

Scott