Dental Scrap - Crude refining

[mlgdave]

Hi everyone, been a LOOOONGGGGGGG time since I have been on. I have Private messaged Lou and Samuel but want to put this up and get some thoughts. I have been reading for a few hours and cant seem to see if this technique will work.

I gather and send in a lot of dental every week, 1200 - 2000 grams every week and am now at a point where I want to do some crude refining before I send in. I have had results vary by about 8-12% from 2 different XRF's I use to test my melted bars. Over a year thats a lotta $$$$

My thoughts are to finely crush the white dental (pfms) to a dust and use nitric to dissolve the material. (I could also melt them and pour them into shot, but my crusher does a fine job of turning it to dust)
- Filter off the pregnant nitric, drop the silver using salt.
- Cement the PD with copper
- There is no PT to speak of in modern alloys so im not concerned about them

My thoughts with the yellow crowns is basically the same, I try to sort as best I can and am usually left with a bar of about 60% Au, and 5-6% PD and of course about 15% silver, but I would do each seperately (yellow from pfms) as the lower % of silver and PD would be done dissolving faster

Hope everyone is well and enjoying the PMs going back up finally

Dave

 

[solar_plasma]

I think here are some answers to your questions:

10k question

 

[Lino1406]

Pd you sell as such or melt it? (which flux?)

 

[4metals]

I think you would be better dropping the Pd from aqua regia and dropping a salt. The salt can be calcined to metal and sold as sponge. I wouldn't melt it. Whomever is buying it will prefer it as a sponge as it will need to be upgraded in purity anyway.