Colour

Pale to bright emerald green

Cause of colour

Chromium

Optical Character

Biaxial positive ( Polycrystalline)

Pleochroism

Not detectable

Colour change

No

Spectrum; no polar, calibration in nm.

Untreated – A strong line in violet at 437 with a weaker line at 433 due to iron. Also a line in deep red at 691 due to chromium and weaker lines at 630 and 655 may also be seen. Treated (Dyed) – Diffuse broad band centred at approximately 650 and in some specimens a weak diffuse 437.

Ordinary ray

Not applicable

Extraordinary ray

Not applicable

Alpha ray

Not detectable

Beta ray

Not detectable

Gamma ray

Not detectable

Emission lines

No

Database reference

GN1.

Notes

The  diagnostic line at 437 due to iron may occur also in colourless jadeite