This gemological tool helps identify certain red, blue, and green gemstones. It is used to determine whether a gemstone is natural or synthetic. It can also detect synthetic blue spinel and dyes in certain gemstones. Most popular and easy-to-use tool for identification. Compact size, portable, and easy to carry. Color: As shown Material: Metal Package Contents: 1 x Filter Only the above package content is included; other items are not included. Note: Light reflection and different displays may cause the color of the item in the image to differ slightly from the actual product. Measurement allowance is +/- 1-3 cm. Note: Due to lighting and screen setting differences, the item's color may vary slightly from the pictures. Please allow slight dimensional differences due to manual measurement.