Gemmology
Etymological, "Gemmology" means "Study of Gems".
The
mysterious charm of gems, their exquisite colours
and their
fires would be sufficient to make them precious; but their rarity,
their hardness and their durability make them more valued.
An experienced gemmologist could determine most stones with a thorough examination with a magnifying glass. But now days, with so many synthetic stones, imitations, and fakes, it is impossible;
in many cases instruments help to identify stones correctly.
- A magnifying glass.
- A polariscope to determine optic character of stones.
- A refractometer to determine refractive indice and birefringence' measures.
- A dichroscope to observe pleochroïc colours.
- A spectroscope to decompose the light on a spectrum.
- A Chelsea filter will allow only extreme red and yellow-green.
- A thermic conductimeter to measure heat's transfer of substances.
- Density liquides help to identify gemstones' spécific gravity.
- Ultraviolets'lights to observe luminescence, a stone reaction under UV rays, away from any other light.
- A binocular to identify inclusions.
Methodes and instruments mainly concerne physical property measurements, caracteristics of several precious stones.
Minerals' properties depend of two factors:
- chemical composition, meaning atomes' composition
- cristalline structure, meaning spacial atomes' arrangement in a mineral.
If the results are still incertain, you can ask for a well known laboratory's services, where research worker have
accurate, sophisticated and costly equipment.
Cécile
CHANCEREL - 19, avenue St-Hubert -
44500 LA BAULE - FRANCE - Phone : 33 (0)2.40.23.82.89 ou 33
(0)6.30.61.76.91