Real diamonds are indicated by sound and light signals. This easy-to-use, handheld gadget measures the thermal conductivity of the tested sample/stone and has an LCD display, LED lights and emits audible sounds to give accurate readings time after time.

The Diamond Selector II will beep and the scale will light up (a green light) or illuminate if the stone is a genuine diamond. It has a 7-second warm-up time and a 150-second shut-off alarm. If the tested stone is a simulant such as cubic zirconium (CZ), nothing happens (except with synthetic moissanite). It incorporates a Large/small switch for testing diamonds over and under 8 points.