Gemlab.UK  Gemmological Research and Education

      HOME         SPECTROSCOPY        SPECTRA DATABASE          NEWS           THROUGH MY SPECTROSCOPE

 

 GEMSTONES   

COLOURLESS STONES

  CS1  

 RED STONES  

  RD1 Dark red

   RD2 Pinkish red

  RD3 Orangy red

RD4 Slightly purplish red

  RD5  Purplish red

PINK STONES 

  PK1 Lilac pink

   PK2 Pink and orangy pink

PK3  Brownish and purplish pink

ORANGE STONES

OR1

  These are the first sections to be uploaded and additional gems will be inserted in them as we proceed

 

Diffraction Spectra of

Green Jadeite

Colour Properties of Green Jadeite

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

None yet

Notes

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

 

 

 

 

 

 

Copyright John S. Harris 2000-2010

 

SPECTRA OF PRINCIPAL COMMERCIAL GEMSTONES

ALEXANDRITE

ALMANDINE GARNET

CHRYSOBERYL

DIAMOND

EMERALD

PERIDOT

RUBY

SAPPHIRE

RED SPINEL

GREEN & BLUE SPINEL

SYN. BLUE SPINEL  & Co. GLASS

SYN. COLOUR CHANGE CORUNDUM

ZIRCON (High type)

ZIRCON (Low type)

Other pages are under construction.