Gemstone Microscope
The gem microscope is one of the most important instruments in gem identification. Its main purpose is to magnify and observe the internal and external features of gemstones. Features that cannot be seen by the naked eye can be magnified through the gem microscope, which helps to identify natural and synthetic gemstones and treated gemstones.
The structure of gem microscope
The main structure of the gem microscope is shown in Figure 1
Figure 1 The structure of a gem microscope
- Eyepieces: When observing gemstones, the operator observes the gemstones through the eyepieces. The commonly used magnifications of the eyepiece are: 10X, 15X, 20X;
- Continuous zoom knob: can be rotated to adjust the magnification, the general adjustment range is: 0.75X-5.0X;
- Object lens: The lens closest to the gemstone, the magnification is generally: 1X, 2X, 3X;
The eyepieces, continuous zoom knob and object lens together constitute the microscope lens. The magnification of the microscope = eyepieces magnification * zoom magnification * object lens magnification.
- Lens holder：The part where the microscope lens is placed is usually in the shape of a ring, and the diameter of the ring matches the lens;
- Focusing knob：Located below the lens holder, the height of the lens holder can be controlled by the focus knob;
- Top light: Turn on the top light source when observing the surface features of the gemstone;
- Bottom light: When observing the internal features of the gemstone, turn on the bottom light source, which is divided into bright field lighting and dark field lighting;
- Side light: Turn on the side light source when observing the internal inclusions of the gemstone or when the light source is not bright enough;
- Light source switchs: Individually control the switch and brightness of the top light source, bottom light source and side light source;
- Microscope base: The top light source, bottom light source, side light source and light source switch are installed in the base, and together constitute the light source system of the gem microscope.
Main functions
- Observe the external characteristics of the gemstone
Whether the surface is worn (Figure 2), the quality of faceting craftsmanship (Figure 3), the quality of faceting polishing (Figure 3), surface texture (Figure 4, Figure 5), joint seams (Figure 6), …
Figure 2 Worn surface
Figure 3 The facet edges are not aligned,and facet polishing lines
Figure 4 Gemstone surface texture
Figure 5 Acid etching marks on the surface of B-grade jadeite
Figure 6: Joint seam
- Observe the internal characteristics of the gemstone
Including the internal structure of gemstones (Figure 7), gas (Figure 8), gas-liquid inclusions (Figure 9), three-phase inclusions (Figure 10)…
Figure 7 Lizard skin-like structure
Figure 8 Gas inclusion
Figure 9 Gas-liquid inclusion
Figure 10 Three-phase inclusion
Microscope maintenance
- Do not apply excessive force to the mechanical parts of the microscope;
- The microscope should be dustproof and shockproof, and should be placed in a box or covered with a lens cover when not in use;
- Do not touch any lens with your hands. If you need to clean the lens, wipe it with lens paper or special lens cloth;
- When not in use, adjust the microscope light to the lowest brightness and turn off the microscope light. When turning on the microscope light source, ensure that the microscope light brightness adjustment knob is at the lowest level; when replacing the bulb, do not touch the bulb directly with your hands to extend the service life of the lighting bulb;
- After use, adjust the objective lens to the lowest point to extend the service life of the focusing knob.
Common faults of gem microscopes and troubleshooting methods
1) The light source of the microscope is not on: Check whether the power cord is loose. If the power cord is loose, please plug it in tightly. If the power cord is not loose, please check whether the fuse is burned out.
2) How to replace a burned-out fuse: There is a spare fuse at the power cord socket. Please take out the spare fuse and replace it.
3) How to clean the lens: Gently wipe it with a cotton pad dipped in a small amount of a 3:7 ratio of ethanol and ether. Be careful not to let the liquid seep into the interior to prevent the lens from falling off;
4) The microscope observation is not clear: Please debug the two eyepieces of the microscope separately. After the debugging is completed, the observation will be clear again.