Help id light colored material from cementation

[Bentfunky]

Apologies in advance if I’m asking too many questions on this forum.

I need help identifying light material.

Last night I cemented suspected PGMs on copper. I did this after getting stannous chloride tests indicating PGM.

Dark material, almost black, precipitated onto copper first. Cleaned material off of copper and placed in separate container.

I then placed copper back into solution to determine if additional material would precipitate. Left it over night. In the morning I noticed a yellow-white material covering copper. See below picture.

<edited out comment that, well, just didn’t make sense. I choose to believe that I never actually wrote it>

What is this?

 

[Lino1406]

Might be gold

 

[Bentfunky]

@ Lino1406, really appreciate the quick reply! Gold would be nice. I guess that I believed gold would be darker.

 

[Bentfunky]

Well, this was unexpected. Was testing a small amount of crushed rock for gold. After dissolving sample, Stannous chloride test was weak positive for gold.

Decided to see if anything would cement out onto copper, so put diluted AR onto mixer/heater. Initially, had a thin layer of precipitate in copper. Liquid turned light green. Since not copper blue yet, washed off precipitate into collecting jar and put copper back into sample jar.

Came back a couple hours later and found this. Put copper in, got a bit more precipitate. Tested with stannous chloride. Negative. Diluted with water. Magic!

Water turned light green again and got a bunch of white precipitate. Guessing this is cupric chloride. Chemistry is so cool!