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GEMSTONE SPECTRA

(EXCEL FILES)

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

YELLOW STONES

YL1

GREEN STONES

GN1 Green

GN2 Yellowish and greyish green

GN3 Bluish green

GN4 Dark and brownish green

BROWN STONES

BN1 Light brown

BN2 Dark brown

BLUE STONES

BL1 Blue

BL2 Greenish blue

BL3 Lavender and indigo blue

VIOLET AND PURPLE STONES

VT - PL Violet and Purple

 Periodically other gemstones will be added to these files

 

 

Diffraction spectra of almandine garnet

See my  DECLARATION OF COPYRIGHT

Colour Properties of Almandine Garnet

Colour

Various shades of red from a brownish to dark purplish red

Cause of colour

Iron - idiochromatic

Optical Character

Isotropic                   

Pleochroism

Not applicable

Colour change

No

Spectrum; no polar Calibration in nm.

617 weak; 576 & 527 moderate to strong and broad. 505 strong to very strong and broad merging with 527 when Fe. content is high. 462 weak to strong as Fe increases.

Ordinary ray

Not applicable

Extraordinary ray

Not applicable

Alpha ray

Not applicable

Beta ray

Not applicable

Gamma ray

Not applicable

Emission lines

No

Database reference

All above in RD5 See also RD1 and RD3 for other red garnets

Notes

RI rises with Fe. RD0323-1.760; RDF0039-1.770; RDF0121-1.784

 

Copyright John S. Harris 2000-2016

 

SPECTRA OF

 PRINCIPAL 

COMMERCIAL GEMS

ALEXANDRITE

CHRYSOBERYL

DIAMOND

EMERALD

GREEN JADEITE

PERIDOT

RUBY

BLUE 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. 

COLOUR FILTERS

 (EXCEL FILES)    

CF1 Basic Colour Filters

CF2 Special Colour Filters

EDUCATIONAL C. D.

  A GUIDE TO THE   SPECTROSCOPE