A - Z Gemstone Menu

Rubellite Gemstone Information

Rubellite is the red variety of tourmaline, similar in colour to ruby from which the name is derived. The most valuable stones have a colour similar to that of a 'good quality ruby'. Higher priced stones have a colour that is fairly consistent when viewed in daylight and artificial light. Less valuable stones turn brownish when viewed in incandescent light (from a filament light bulb).

Inclusions are common in rubellite and seem to appear more in stones with a darker hue.

Major source locations for rubellite include: Africa (Nigeria), Afghanistan, Brazil, Madagascar and the USA (California)

Physical Properties

Stone type:
A variety of the tourmaline group.
Crystal System:
Trigonal.
Chemical Composition:
A complex borosilicate of aluminium, magnesium, iron, calcium and alkali elements.
Colour:
Deep pinkish-red colour or red that may have a brown or violet tint.
Lustre:
Vitreous.
Pleochroism:
Dichroic: Strong in most stones, showing a variation in colour depth, but may be absent in others.
Dispersion:
Low.
Hardness:
7 to 7½ on the Mohs' scale of hardness.
Toughness:
Good, but may be damaged by thermal shock (sudden temperature change).
Cleavage:
Very uneven.
Density in gm/cc:
3.0 to 3.1
Double refraction:
Yes.
Refractive index:
1.62 to 1.64

Common Treatments

Tourmalines may be heat-treated or irradiated to improve their colour. Treated stones are normally stable, but when subject to prolonged exposed to heat or strong light, they may fade.


Top of Page | Gem-Guide Home