Our headline is actually a comment made by our Lab Manager, Olga Yankov. Our customer sent in a ring they assumed was platinum as part of a lot scheduled to undergo our Premium Stone Removal Process.
During a spot check the ring appeared to be white gold or most probably platinum. The piece was put into the acid with the stone job. After the lot was processed and all stones were removed the ring remained. The ring came out of the acid totally unscathed or marked in any way. Not a scratch. Our Lab Manager was intrigued. She brought it to X-ray and it was discovered to be Cobalt.
We don’t often see this metal, but have noticed it is becoming more and more common. Cobalt is a highly durable alloy, four times harder than platinum but believe it or not, lighter weight. Cobalt is actually harder than Titanium but not as hard as Tungsten. A Cobalt ring has a much lighter, whiter hue than other metals, that is why many mistake it for platinum or white gold. Cobalt rings do not tarnish.