If you cannot find what you are looking for, get in touch and we will be glad to help.
Every study begins with knowing exactly what a stone is. Our identification work combines classical gemological instruments with modern spectroscopy to determine the mineral species and variety of cut and rough material without damaging the sample.
Measurements are recorded against reference standards, so that results can be reproduced and compared across stones, sessions and laboratories.
Refractive index, birefringence and optic character are measured on a polished facet and checked with the polariscope and dichroscope.
Separating look-alike species such as ruby and red spinel, or sapphire and tanzanite.
Fast, non-destructive and diagnostic for most faceted stones.
Density is determined hydrostatically by weighing the stone in air and in water.
Useful for rough, cabochons and carvings where refractive index readings are difficult to obtain.
Independent of surface polish and suitable for stones of almost any shape.
Laser and infrared light probe the vibrations of a crystal structure, producing a spectrum that acts as a fingerprint.
Confirming species, identifying inclusions and recognising polymers or other fillers.
Highly specific, and works on mounted stones as well as loose ones.
Faceted stones, cabochons, rough crystals, beads and carvings can all be examined. Mounted stones can usually be tested too, although some measurements are easier on loose material.
No. The identification methods we rely on are non-destructive and leave the stone unchanged.
Use the contact page to describe the material and what you would like to learn, and our team will advise on the appropriate examination.
Consistent description of colour, clarity, cut and weight under controlled conditions.
Read More
Locating and modelling internal features in rough and polished stones.
Read More
Relating proportions and symmetry to brightness, fire and scintillation.
Read MoreAdvancing the understanding of gemstones through science, precision and innovation, from their formation deep within the Earth to the finished stone.
© 2026 Ann Gems Gemstone Research Institute. All rights reserved.
+1 937 803 2459
Make an Inquiry