Simple gems professional identification method

Many people think that jewelry appraisal is a profound knowledge, but it is not. The gem identification features can be determined with a few small instruments. In addition to some knowledge of the precious stone and color of the gem, you can also become an expert in jewelry appraisal.

Ruby's English name is Ruby, derived from Latin, meaning red. Because of its composition containing chromium and red to pink, the higher the content, the more vivid the color. Blood red rubies are the most treasured by people, commonly known as "pigeon blood red."

In the Bible, rubies are the most precious of all gems. Ruby's hot redness makes people always associate it with passion and love. It is known as the “stone of love” and symbolizes passion, love, beauty, eternality, and constancy. Ruby is the birthstone of July.

According to legend, the Burmese warriors in the past cut a small c in their bodies and put a piece of ruby ​​into the mouth. They think that this can achieve the purpose of invulnerability.

The main producing areas are Myanmar, Thailand, China, Sri Lanka, Tanzania, Vietnam and so on.

The following is an excerpt from the national standard "GB/T-16553 identification of jewelery and jade", let us have a one-to-one correspondence between the instrument and the content!

(The following method also applies to other gemstones)

English name:ruby

Mineral name: Corundum.

Chemical composition: Al2O3; may contain Cr, Fe, Ti, Mn, V and other elements.

Crystalline (crystal properties): trigonal. Crystal form: hexagonal columnar

Common colors: red, orange red, purple red, brown red.

Mohs Hardness (The instrument used is a hardness pen): Standard No. 9 hardness. (between topaz 8 and diamond 10).

Density (the instrument used was a water weigher): 4.00 (±0.05) g/cm3.

Optical characteristics (the instrument used is a polarizer): Heterogeneous, monoaxial, negative light. (The outer ring shows the visual effect of full dark when the upper and lower polarizers are in the orthogonal polarization, and the inner circle shows the position of the gems)

Polychromaticity (the instrument used is Iceland Dichroic Mirror): strong, purple, orange-red.

The refractive index (the instrument used is a refractometer): 1.762 to 1.770 (+0.009, -0.005).

Ultraviolet fluorescence (the instrument used is an ultraviolet fluorescent lamp): long wave: weak to strong, red, orange red. Short wave: no to medium, red, pink, orange, a few strong red.

Absorption Spectrum (The instrument used is a spectroscope): 694,692,668, 659 nm absorption line, 620-540 nm absorption band, 476, 475 nm strong absorption

Line, 468nm weak absorption line, violet absorption.

Magnification examination (the instrument used is a magnifying glass or a microscope): Filament, acicular inclusions, gas-liquid inclusions, fingerprint-like inclusions, envelops, negative crystals, crystal inclusions, growth patterns, growth ribbons, double Crystal pattern. Dark-field lighting, horizontal lighting, and bright-area lighting are recommended.