It is because there are cracks or inclusions in the gem that cause light scattering and refraction, thus forming white light. This pink gem may be ruby, ruby and other red gems, because these gems are red in color and are often used to make jewelry. Illumination is a common gemstone polishing technology, which can make the light reflection of gemstones more uniform and improve the color of gemstones. In the process of lighting, different lights will be used to illuminate the gem, so as to observe and identify its quality and characteristics.