The principle of the night pearl?

The so-called "luminous pearl" refers to a substance that can emit visible light under the excitation of external energy, and the light emitted is also called "phosphorescence". Its luminescence principle is closely related to trace impurities in mineral crystals. This kind of fluorite, which can glow after heating, is also called "the night pearl" by the people.

In physics, the luminous principle of the luminous pearl is that the phosphorescent stone absorbs external energy after being irradiated by sunlight, and then releases this energy in the dark, forming a silvery white luster.

The main materials of the night pearl are fluorite, calcite and some diamonds, among which fluorite is the most common.

Extended data:

Fluorite is also called fluorite, fluorite powder and fluorite powder. It is a mineral with equiaxed crystal system, and its main component is calcium fluoride (CaF2). There are many impurities, and Ca is often replaced by rare earth elements such as Y and Ce. In addition, it also contains a small amount of Fe2O3, SiO2 and trace amounts of Cl, O3 and He.

Fluorite in nature often presents bright colors, and some can emit fluorescence. Mohs hardness 4, lower than steel, easy to scratch, brittle, sweet, astringent and non-toxic. Melting point: 1270- 1350℃. Density: 3. 18g/cm? Refractive index: 1.434.

Formation principle

Fluorite comes from volcanic magma. During the cooling process of magma, the gas-water solution separated from magma contains many substances, mainly fluorine. In the process of the solution rising along the fracture, the temperature and pressure decrease, and fluoride ions in the gas-water solution combine with calcium ions in the surrounding rock to form calcium fluoride, and fluorite is obtained after cooling and crystallization.

It is an accessory mineral of granite, pegmatite and syenite, and fluorite can also be found in the pores around the volcano. It also exists in carbonate rocks and alkaline intrusive rocks. Deposited in hydrothermal veins and stratabound deposits. Fluorite will act as an adhesive at the natural joints of sandstone.

Natural distribution

The main fluorite deposits are located in Cornwall, castleton, Derbyshire and Durham, England. Dom in France; Mont Blanc, Switzerland; German black forest; Spanish asturias; Daringorsk, Russia; Karaoba, Kazakhstan.

Hunan, China; Chihuahua, Abela, durango; New york, Ohio, Illinois, Tennessee, Colorado, New Mexico; Lake Ontario, British Columbia, Canada; Vanuco, Peru; Namibia; Pakistan.

References:

Baidu encyclopedia-fluorite