Brilliant gems are brilliant and colorful, which are brought out by the color, luster, transparency, refraction, and cut of the gems.
As gems are crystallized, they often contain inclusions, double crystallines, lattice structure defects, etc., which cause light interference, diffraction, scattering, and other phenomena. Some special optical effects will appear under illumination, which makes the gems more beautiful and also Increases the value of gems.
Common special optical effects include starlight effect, cat’s eye effect, color-changing effect, moonlight effect, play-of-color effect, Venus effect, luminous effect, etc.
(1) Star effect: also known as star effect. When the arc-shaped cabochon gem is irradiated by light, the surface of the gem presents an optical effect of rendezvous, six-shot and up to twelve-shot star-like rays, like stars in the night sky.
(2) Cat’s eye effect: When the camber gem is irradiated by light, the front and back of the gem present a bright band of light. When the gem is rotated, the band of light moves, resembling cat-eye slender pupils, which is called the cat-eye effect or play-of-color effect.
(3) Color-changing effect: The gems show different colors under different light sources such as sunlight or light, which is called the color-changing or color-changing effect of gems.
(4) The play-of-color effect is also called the play-of-color effect. That is, under the illumination of white light, the same gemstone ring surface shows a phenomenon of multi-color changing flashes at the same time. When turning the gem or the light source, you can see that the color of the gem is constantly changing, sparkling and charming, with red, orange, yellow-green, and other color spectrums.
(5) Moonlight effect: Moonstone is a micro-plagioclase with lattice-like double crystals. Two sets of double crystal grains approximately perpendicular to each other scatter the incident light. The dense scattered light is concentrated together, showing a hazy halo, like Moonlight, so it is called the moonlight effect. The plagioclase with moonlight effect is called moonstone.
(6) Venus effect: transparent and semi-transparent gemstones, when there are many opaque tiny solid inclusions inside, they will be shining by reflection under the light. This phenomenon is called the Venus effect, also known as the placer gold effect, such as Venus Quartz, etc.
(7) Luminous effect: gems with fluorescence or phosphorescence are called luminous gems, among them, gems with strong phosphorescence are commonly known as “night pearls”. Such as red fluorescence of ruby, blue fluorescence of scheelite, blue phosphorescence of the diamond, etc.