Testing white gold vs sterling silver

Jewelry Discussion
1

I’ve been using an off the shelf testing kit for gold: three acids
10K, 14K and 18K, 3 needles of yellow gold 10-18K, and a touchstone.
These have proved useful for testing unknown yellow gold for trade
from customers and seems to indicate properly. However, if I draw a
strips of 10K white gold, the 10K test needle, and sterling, either
the old fashioned copper alloyed or Argentium, these lines test
positive too and do not dissolve with the 10K acid.

I need to be able to test 10K and 14K white without ambiguity,
particularly against sterling silver. There is a lot of Rhodium
plated sterling that looks like white gold, and it is impossible for
me to tell visually by eye when the Rhodium is filed off if it is
silver or gold. How do I do this (other than by guessing density)?
Any thoughts would be appreciated.

Joris

2

Get a bottle of drugstore, antiseptic, iodine - the least diluted
solution available. Apply to metal after Rhodium has been filed away.
White gold my show some minor discoloration but sterling will go
black.

Copper and yellow gold are pretty much unaffected.

Try it a few times on some scrap pieces and you’ll quickly get to
where you can tell the difference.

Les Brown

3

Use pure nitric acid on the drawn lines at the touchstone. Silver
will quickly dissolve while 14k white gold will have little change in
color and for 10k white gold will return red in color.

Marvel