How to identify jade by checking cracks? You can check the gap. Take the jade to a bright place and observe it with a magnifying glass. The true gap is slightly transparent, the color is lighter, and the false gap has pigment deposition and the color is darker. 2. Observe how to identify jadeite. Identify the authenticity of jadeite under the lamp, or observe it under the lamp. Take the jade to a bright place and observe it under the lamp. Real jade can be seen with asbestos, cracks and other defects, while fake jade is very clean and pure inside. 3. Fluorescence test How to identify jadeite to identify the authenticity of jadeite, and you can also conduct fluorescence test. Observe the jade under ultraviolet light. Real jadeite basically does not emit light or emits a small amount of fluorescence under ultraviolet irradiation. The fake jade gives off bright light as a whole after bonding.