This gemstone testing equipment is not only a diamond tester, but also a multi-gemstone tester. It can detect whether a gemstone is real or fake, including: diamond, sapphire, ruby, crystal, agate, jadeite and other gemstones of different sizes. If the number of lights is equal or above 9, and it beeps, it means the diamond is true. If the lights are at about 9 and it beeps, it means the sapphire is real. If the number is 6.5-7, it means the agate is real. If the number is 7-8, it means the crystal is true. If the number is 6-7, it means the jade is true. Before testing: 1. Put the battery into the tester. 2. Remove the probe cap. 3. Turn on the switch. 4. Make sure only one light illuminates on the scale. 5. Make sure the "Ready" light comes on. 6. (If you are testing the diamond, then you should turn on the number of lights corresponding to the interior temperature and the weight of the diamond.). 7. (If you test other gems, you'd better calibrate the probe, method: placing the probe vertically on a glass, Product size: 16 4 2.2 cm weight: 100g Power required: 1x 9V battery (not included) If you have any problem about testing, please contact us, we would love to help you. of the product If the number of lights is 9 or more, and it beeps, it means the diamond is true. If the number of lights is of 9 and it beeps, it means the sapphire is real. If the number of lights is 6.5-7, it means the agate is real. If the number of lights is 7-8, it means the crystal is real. If the number of lights is 6-7, it means the jade is real. Before Testing: 1. Put the battery into the tester. 2. Remove the probe cap. 3. Turn on the switch. 4. Make sure that Only one light comes on on the scale. 5. Make sure the ready light comes on. 6. (If you are testing the diamond, then you should turn on the number of lights corresponding to the inside temperature and the weight of the diamond.) 7. (If you are testing other gems, you'd better calibrate the probe before testing, method: placing the probe vertically on a piece of glass, then adjusting the light to 5, then placing the probe on the gemstone to test.) 8. The test is ready. NOTICE: Regardless of the stone you are testing, the probe needle and the object under test must be at an angle of 90. When testing the diamond, your right index finger should continue to touch the metal panel on the back of the tester, without touching the panel if you are testing other gemstones. Do not test metal. Do not wear gloves. Product size: 16 4 2.2cm. weight: 100g. Power required: 1x 9V battery (not included). Package contains: 1x diamond tester