Why would one tested Sterling discolor fingers and another not?

Hi there. I have some sterling rings I just bought from a vendor (we will call them Vendor A) and they are turning customer’s fingers green. These same customers are wearing other sterling rings that they have had for years AND they have now tested new ones from yet another vendor (Vendor B) and their personal rings and Vendor B’s rings haven’t discolored them at all. These are people that wear only sterling and we aren’t just talking about a few, I have feedback (and green finger pix) from about 25+ people. Vendor A’s rings were tested and show to be true sterling. So for the life of me (and the life of Vendor A’s) we can’t figure out why one sterling would discolor and the other not. Why would people who have always worn sterling suddenly get discolored from Vendor A’s rings? I have never had this happen before in the 15 years I have been selling sterling rings (bought from at least 6 different vendors).

Further info, Vendor A is USA based and had their sterling tested here as well.

Recently had an experience where one of my silver rings turned my own finger green…

I made it in Argentium Silver, however it went away with wearing it a few times.

My troubleshooting were either:

  • Not proper cleaning of the ring, polishing residue or other chemicals still on the ring
  • Grind of a small bit inside the shank, when casting silver a tiny layer of copper can reside the at the surface.

Recently got a electocleaner, which i will add to my finishing workflow, and see if this will eleminate my problem onwards.

Perhaps Vendor A gotta be even more strict about cleaning the rings, and perhaps vendor B gives his rings a layer of silver plating for final finish etc etc… Would say it comes down to the last stages of prepping the ring before selling

Looking forward to hear what people have to say for my own sake aswell!

It could be due to the second batch of rings (Vendor B’s) being pickled more than the second (from Vendor A). Sterling alloys contain a small amount of copper, which discolors the skin with a characteristic greenish stain. If the ring is pickled for a fairly long time, the copper towards the surface is removed by the solution, leaving the pickle with a bluish tinge and the ring with nearly pure silver where it contacts the finger. If the rings were gold, this would be called “depletion gilding”; it makes a gold alloy look like a higher-karat one. I’m not sure if there’s an equivalent term for silver alloys.

It could also be that Vendor B’s rings were rhodium-plated, which forms a barrier between the sterling and the finger.