What the heck is this?

[leavemealone]

Most of you that know me,know I've been processing for a few years.I just started processing pins less than a year ago,so I know I haven't seen everything.Well one of those things revealed itself tonight.It looks like it could be precipitated silver or salt.Let me explain what happened then maybe it will help answer what it is.I bought some used pins on ebay.I have never seen pins exactly like this before,which is no big surprise,given the thousands of different kinds of pins out there.I put them in my 4000ml erlenmeyer and added about 2500ml of muratic.This is my favorite way to process pins,concidering I have had a lot of problems with adding peroxide in the past,I tend to get too impatient and add too much,losing my gold in solution.So I put the flask on the hotplate last night.This morning,it was lightly boiling,which is normal,but the solution was almost perfectly clear.Thats the first wierd part.Normally after one night,you cant see 1 inch into the solution it is so saturated with copper.Then I noticed the pins were jet black.So I turned off the hot plate while we were out today.When I started to diagnose the problem tonight I noticed what appears to be thousands of tiny white "hairs" on the pins and the solution is still clear.They are crystalized and about 1/4 inch long.I assume it is silver,but I don't dare act on it until I get a diagnosis from the doctor....lol.So here ya go guys,start diagnosing.
Thanks
Johnny

 

[ck]

deleted

 

[semi-lucid]

There's a possible Beryllium hazard with hard copper, sping loaded connectors. Be careful to not breath any dust from the residue.

semi

 

[Harold_V]

and added about 2500ml of muratic.

That pretty much rules out the possibility of silver being involved.

I think I'd look towards zinc being the culprit. It would have precipitated any copper that may have been dissolved, which would account for the clear solution. Brass pins are comprised of a healthy percentage of zinc.

Did you think to check the pH of the solution? That may have been an indicator that you had exhausted the HCl, allowing the dissolved zinc, which was now quite concentrated, to grow the crystals you speak of. Just a thought, mind you.

Harold

 

[Oz]

Rock on semi-lucid, I wish more people paid attention to beryllium when they hack, beat, and pull on motherboards without a respirator.

 

[nicknitro]

I see a faint layer of gold on top, do you intend to filter this solution or vacuum off the gold? Either way, I am interested in the outcome.

In my prior flops, I think soluabilty has been a great learning experience in what I was refining.

I think I shall post a topic dealing with dirty nitric solutions, to present some answers to a few newbie's questions. Give me time to resize the pictures.

Thanks and Good Luck,
Nick

 

[leavemealone]

Brass pins are comprised of a healthy percentage of zinc.

That would explain a lot.They could have no gold on them at all.That would explain the black color on the outside of the pins and explain the crystalisation.When the solution was boiling the solution became supersaturated,and as it cooled,the elements self precipitated.

Did you think to check the pH of the solution?

No I didnt,and I do not have a kit.But I should be able to put a few drops on a piece of copper and watch for a reaction right?If the solution is zinc saturated then it wouldnt allow any of the copper to be digested right?
Well heres a twist I just thought of.When I recieved the pins a while back,I put a couple of them in nitric,and ended of with beautiful gold foils......so that throws my having no gold theory out the window.Well for now I am going to pour the acid back into the container it came from,mark it,and keep it until later.If it is zinc saturated,then maybe I could use it later for an emergency precipitant.In the mean time I'll just add clean acid and move on,unless someone else disagrees.
You know its ashame I dont have a spectro machine.I have all of these lamps and no way to use them.I could tell,with amazing accuracy,what the problem is,if I had that machine....lol.