The assay / refining lab.....second time around

4metals · Aug 19, 2015

It's been there for a while.
http://goldrefiningforum.com/phpBB3/viewtopic.php?f=85&t=9528

Palladium · Aug 19, 2015

I never was much good with the Dewy Decimal system.

guldspecialisten · Oct 7, 2015

Very interesting post.

I handle impure silver which contains small amounts of gold and I have been looking for an exact way of assaying this silver for gold. The gold content is often around 1g for every kilo of silver.

I have tried to find the gold content by digesting 5 grams of the silver in nitric acid, but the brown residue is often contaminated by a reddish/violet precipitate probably from other metals in the silver.

Would it help to dry the precipitate in a piece of sheet lead, fold the lead and cupel it, or is there a better approach to this?

guldspecialisten · Oct 7, 2015

4metals said:
OK nugget here's the spreadsheet in Excel 2003

A few things, first the sheet is protected so you can only input data into the yellow colored cells AND you can change the correction factor. I put a correction factor of .999 in the sheet but a good assayer runs a correction with every furnace load. That being said, you can run a proof and put your own correction factor in. If you need to know how to run proofs let me know and I'll post the technique.

The sheet is also locked so you can't accidentally erase or delete the formulas but it is not password protected so you can unlock it and edit it if you like.

Hello 4metals. I would also like a copy of your spreadsheet in Excel if you don't mind. When I click the link i get: The selected attachment does not exist anymore.

Can you repost it?

Thanks in advance

4metals · Oct 7, 2015

Would it help to dry the precipitate in a piece of sheet lead, fold the lead and cupel it, or is there a better approach to this?

Yes cupellation would be my first choice.

I would also like a copy of your spreadsheet in Excel if you don't mind. When I click the link i get: The selected attachment does not exist anymore.

This isn't exactly it but it may do unless you need gold with silver by difference. Then I will have to dig a bit.

View attachment Fire assay calculator.xlsx

guldspecialisten · Oct 9, 2015

Thank you so much 4metals. I will try to cupel the gold precipitate.

I would also like a copy of your spreadsheet in Excel if you don't mind. When I click the link i get: The selected attachment does not exist anymore.

This isn't exactly it but it may do unless you need gold with silver by difference. Then I will have to dig a bit.

If you don't mind digging a bit I would appreciate if you would re upload the original gold with silver by difference spreadsheet or similar.

I appreciate your help.