1, 10 times magnifying glass. 10 magnification magnifying glass is an essential tool for identifying gems. In fact, pawnbrokers will use it when appraising various items. 10 Magnification Magnifier consists of three lenses. The qualified 10 magnification magnifier should have high definition, which can eliminate the spherical aberration and chromatic aberration that affect the observation of gems. When in use, hold the magnifying glass in one hand and put it in front of one eye, and hold the jewelry holder with the index finger and thumb in the other hand (if it is bare stone, use gem tweezers) and approach the magnifying glass until the eye can clearly observe the gem. For loose diamonds, carefully clamp them with tweezers to prevent them from falling.
2. Pen flashlight. The spotlight-pen flashlight is a kind of lighting tool, which can be used as a lighting power supply in identification and is very important for observing the inclusions and structures on the surface and inside of gems.
3. Refractometer. Refractometer is a very important gem identification instrument, and its design purpose is to read the refractive index of the gem to be measured quickly, accurately and lossless. Each gem has its corresponding refractive index, such as jadeite 1.66, ruby and sapphire 1.762~ 1.770, aquamarine 1.577~ 1.583, tourmaline/kloc. By accurately measuring the refractive index of a gem, we can roughly judge what kind of gem the gem to be tested may be, and then combine with other identification methods to determine the species of the gem.
4. Gem microscope. Gem microscope is generally one of the necessary identification and testing instruments in gem laboratory. Gem microscope observes gems by using the working principles of dark field illumination, bright field illumination and vertical illumination through the built-in light source. The magnification is generally 10 to 70 times, which plays a great role in distinguishing natural gemstones from synthetic gemstones and imitation gemstones, and is also very effective in observing the purity of gemstones. In the gemological professional appraisal room, the gem microscope can also measure the approximate refractive index and absorption spectrum of some gems.
5. Polarizer. Polarizer plays an important role in distinguishing isotropic body, anisotropic body and polycrystalline body.
6. Diamond thermal conductivity meter. In pawn shops, the most common jewelry and jade ornaments that pawnbrokers contact are diamond ornaments, and the diamond thermal conductivity meter is very effective for distinguishing diamond ornaments from their imitations. However, with the emergence of synthetic silicon carbide (also known as moissanite or Mosanite), it is necessary to be extra careful when measuring diamonds with thermal conductivity meter, because synthetic moissanite also has the same diamond reaction. Therefore, pawnshops have to verify other appraisal indexes, make comprehensive analysis and calculation, and draw the appraisal conclusion when they encounter diamond jewelry pawn business.
7. Charles filter. Charles color filter consists of two color filters, which are characterized in that the color filters can only pass dark red and yellow-green light, while all other light is absorbed. Charles filter was first used to distinguish natural emeralds from their imitations, because emeralds are red under the filter, while other green imitations are still green. In addition, it is also practical in the detection of artificially dyed gems and synthetic gems. For example, dyed jadeite and blue glass are red under the color filter, but some gems are not obvious under the color filter. For example, the color change of dyed quartzite is not obvious under the color filter. Therefore, the identification results of Charles filter are generally only of reference value.
8. Ultraviolet fluorescent lamp. The function of ultraviolet fluorescent lamp is to detect whether a gem has fluorescence and phosphorescence. Natural rubies show beautiful red color under ultraviolet fluorescent lamp, and most diamonds also have fluorescent display of various colors under ultraviolet lamp, which plays a certain enlightening role in gem identification.
9.Mosanite (synthetic silicon carbide) detector. Mosanite (synthetic silicon carbide) detector is an instrument specially used to identify Mosanite (synthetic silicon carbide Sic), which is based on the fact that diamonds and Mosanite have different properties in near ultraviolet. Its working principle is basically similar to that of a diamond thermal conductivity meter, and it also contacts the surface of a gem through a contact probe. If it is Mosanite (silicon carbide), the red light on the instrument flashes and chirps. If it is diamond, the green light is on but no sound is made.
10, electronic balance. Used to measure the specific gravity of gems. Different gems have different densities. For example, the proportion of ruby and sapphire is about 4, that of jadeite is 3.34, and that of nephrite is 2.95. Sometimes, only measuring the specific gravity of gems is very effective for identifying gems.
There are also many gem identification instruments used in gemology, such as tweezers, UltraFire WF- 50 1B flashlight (Kerry lamp), refractometer, spectroscope, dichroic mirror and polarizer.