Gemstones are natural, beautiful, durable and rare. There are some gems that, by virtue of their unique beauty, make themselves the "treasure of treasures". The special optical effects of gemstones refer to the strange optical phenomena that occur when they are subjected to the interference and diffraction of light. The main ones are the following, let us look at them together.

Color change effect

The color change effect is also known as the traveling color effect, or the traveling color effect. It is a phenomenon in which the same stone shows multiple color shifts at the same time when illuminated by white light. When the stone is turned or the light source is turned, the color changes constantly, with a variety of colors such as red, orange, yellow and green. The most famous of the color-changing effects is the opal.

                                                                                                            Australian Opal                                                                                                                                                                            

Black Opal

Australian Black Opal

Australian Black Opal

Mexican Fire Opal

Canadian colored chrysoberyl

Colored Chrysolite in the St. Mary's River Gorge, Canada

Moonlight Effect

When a stone such as a moonstone is turned to a certain angle, a blue or white floating light is visible on the surface of the stone, which appears to be hazy moonlight. This effect is known as the moonlight effect.

Starlight Effect

Also known as the starburst effect or starburst graphic effect. The optical phenomenon of a curved convex gemstone that, when exposed to light, exhibits a four-, six- and up to twelve-shot starburst of light rendezvous, resembling the starburst in the night sky. Common varieties with the star effect: pink crystals, rubies and sapphires, garnets.

Color change effect

The phenomenon in which the color of a gemstone changes according to the spectral energy of the incident light or the wavelength of the incident light is called the chameleon effect, which simply means that the gemstone exhibits significant color differences under different light sources. The most famous of these is the chrysoberyl, known as the "alexandrite" or "alexandrite". Other stones with a color-changing effect include sapphires, garnets, spinels, and amber.

Halo effect

Two conditions are both known as the halo effect.

(1) When a stone such as labradorite is turned to a certain angle, the whole sample lights up and can show blue, green and various colors of gold, yellow, purple, red, etc., which is called the halo effect.

(2) The color of pearls is a neutral color of body color, companion color, and halo color. The halo color of pearl refers to the driftable iridescence formed on the surface of pearl or under the surface layer, which is observed from the light reflected from the surface of pearl, and the special luster formed by the reflection interference of the pearl layer on the subsurface of pearl to the light and other comprehensive effects.

Alluvial gold effect

Gems such as sunstone contain a large number of lustrous mineral flakes inside, which reflect a red or golden reflection when the stone is turned, known as the aventurine effect, also known as the Venus effect. Examples include aventurine quartz, sunstone, obsidian, aventurine, etc.

Thin film interference effect

In some gemstone crystals, there are extremely thin cleavage surfaces inside, and the optical effect of light passing through the cleavage surfaces to produce interference, causing the cleavage surfaces to show a colorful glow, is called the thin film interference effect.

Luminous effect

Gems with fluorescence or phosphorescence are called luminescent stones, and those with strong phosphorescence are known as "luminous pearls". The red fluorescence of rubies, the blue fluorescence of scheelite, and the blue phosphorescence of diamonds are examples.

Cat's Eye Effect

Arched stones show bright bands of light on their surface when exposed to light, and when they are turned, the bands move, resembling the slender eyes of a cat, called the cat's eye effect. The cat's eye effect can be seen in many common stones, such as chrysoberyl, quartz, aquamarine, sillimanite, sapphire, tourmaline, etc. It should be noted that the term "cat's eye" refers only to "chrysoberyl with the cat's eye effect", and that any other gemstone with the cat's eye effect must be referred to by the name of the gemstone type.