JZK Portable Electronic Diamond Tester Pen for Diamond, Sapphire, Ruby, Crystal

If the number of lights equal or exceed 9, and it beeps, it means the diamond is true. If the number of lights is 9 and it beeps, it means the sapphire is true. If the number of lights is 6.5-7, it means the agate is true. If the number of lights 7-8 , it means the crystal is true. If the number of lights is 6-7, it means the jade is true. Before Test: 1. Put the battery into the tester. 2. Take off the probe cap. 3. Turn on the switch. 4. Make sure just 1 light light up on the scale. 5. Make sure the " ready lamp" light on. 6. (If you test diamond, you then need to turn on the number of lights corresponding to the indoor temperature and diamond weight. ) 7.

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