Usage of Instruments
- Refractometer: It is based on the principle of "total internal reflection". It is used to determine refractive index, optic character, optic sign and optic axis direction of gemstones.
- Polariscope: It is used to find the optic character, optic figure and to detect pleochroism of gemstones.
- 10x Loupe: It is used for diamond clarity grading, inspection of internal and surface features of gemstones.
- Microscope: It is used to find minute inclusions and blemishes of gemstones.
- Dichroscope: It is used to detect pleochroism and optic axis direction of gemstones.
- Chelsea Filter: This instrument normally indicates the coloring elements present in certain green and blue color gemstones, namely emerald and spinel.
- Spectroscope: This instrument helps in identification of gemstones by absorption spectrum and detects treatment like dyeing.
- U.V. Lamp: It detects fluorescence and phosphorescence and helps to detect treatments done on the stones.
- Reflectivity Meters: It is used to quickly determine refractive index of a gemstone.
- Thermal Probe: This instrument is used to differentiate diamond from its simulant mainly from synthetic moissanite through head conduction process.
- Advanced Techniques: These are some of the advanced instruments used to identify gemstone, treatments and source of its occurrence.
Organic Gemstones
Inorganic Gemstones
- Andalusite
- Apatite
- Azurite
- Benitoite
- Beryl
- Calcite
- Chalcedony
- Chrysoberyl
- Chrysocolla
- Corundum
- Cuprite
- C.Z.
- Danburite
- Diamond
- Diopside
- Dioptase
- Dumortierite
- Ekanite
- Enstatite
- Epidote
- Feldspar
- Fluorite
- Fuchsite
- G.G.G.
- Garnet
- Hematite
- Idocrase
- Iolite
- Jade
- Kornerupine
- Kyanite
- Lapis Lazuli
- Malachite
- Natural Glass
- Opal
- Peridot
- Prehnite
- Pyrite
- Quartz
- Rhodochrosite
- Rhodonite
- Sapphirine
- Scapolite
- Serpentine
- Sillimanite
- Sinhalite
- Sodalite
- Sphene
- Spinel
- Spodumene
- Strontium Titanate
- Sugilite
- Synthetic Moissanite
- Synthetic Rutile
- Taaffeite
- Topaz
- Tourmaline
- Turquoise
- Y.A.G.
- Zircon
- Zoisite