Detects if it is a Diamond, Moissanite, or not.
It has an alert system with a beep, when you touch metal instead the stone always if you handle the jewell with your hand, and take the pen on the two little rectangles in both sides with the other hand.
If the stone is warm to wear it, you have to wait until gets normal temperature. If you donīt wait you can have an error.
It works with 3 batteries AAA (included).