There are many diamond simulants in existence. Simulants are other kinds of stones that have the appearance like diamonds, but are not diamonds. One of the latest is moisannite which will even fool conventional thermal diamond testers.

Darryl had excitedly come into our store asking us if what he found was a diamond. He had already gone to another jewelry store and they used a diamond tester which said it was a diamond. They told him that there are simulants like moisannite that will register as a diamond and that you need additional equipment to verify if it really is a diamond and not a moisannite.

We first used our diamond tester and it did indeed register as a diamond. As carbon based simulant, moisannite will have similar thermal conductivity as diamonds and will read positive on diamond thermal testers.

Using the moisannite tester it then registered as a moisannite and not a diamond.

Darryl was disappointed. Unfortunately it was not a diamond. Fortunately he did not  pay for it.

Russell Oshita
The Diamond Specialists Inc.
Diamonds Hawaii