Gemsdat
 

                Home            Gemstones

 

     

INVESTIGATIONS

Stone

RI min

RI max

Biref min

Biref max

Dens min

Dens max

Colour

Locality

Info

nx min

nx max

ny min

ny max

nz min

nz max

Spectrum

UVS

UVL

Reference

Gypsum

1.52

1.52

 

 

2.31

2.31

pink (dyed)

 

14.32ct, cabochon, dyed, spot RI

 

 

 

 

 

 

2 bands in the green

patchy yellow-orange

patchy yellow-orange

Gems & Gemology 2009 Winter, p309-310

 

TABLES

Stone

RI min

RI max

Biref min

Biref max

Dens min

Dens max

nx min

 nx max

ny min

ny max

nz min

nz max

Reference

Gypsum

1.52

1.53

0.01

0.01

2.3

2.33

1.520

1.520

1.523

1.523

1.530

1.530

Joel Arem, Color Encyclopedia of Gemstones, 1987 

Gypsum

1.52

1.52

 

 

2.2

2.4

 

 

 

 

 

 

John Sinkakas, Gemstone and mineral data book,1972 

Gypsum

1.52

1.529

0.009

0.009

2.2

2.4

 

 

 

 

 

 

Bestimmungstabellen für Edelsteine, Birgit Günther, 1981 

Gypsum

1.52

1.53

0.009

0.01

2.2

2.4

1.520

1.521

 

 

1.529

1.530

Gemme, Dati per l'identificazione, P. De Stefano et al, 1993 

Gypsum

1.52

1.53

0.01

0.01

2.3

2.33

 

 

 

 

 

 

http://www.gemmology.be 

Gypsum

1.52

1.53

0.01

0.01

2.28

2.35

 

 

 

 

 

 

Tabellen zur Edelstein-Bestimmung, Pschichholz FGA, 1975 

Gypsum

1.52

1.53

0.01

0.01

2.3

2.33

1.520

1.520

1.523

1.523

1.530

1.530

http://www.geminterest.com 

Gypsum

1.52

1.53

0.01

0.01

2.3

2.33

 

 

 

 

 

 

Gems, R Webster, 5th edition 1994 

Gypsum

1.52

1.53

0.01

0.01

2.3

2.33

 

 

 

 

 

 

Tables of Gemstone Identification, Roger Dedeyne, Ivo Quintens, 2007 

Gypsum

1.52

1.53

0.008

0.011

2.28

2.35

 

 

 

 

 

 

Gemmo.eu 2013

Gypsum

1.521

1.531

0.01

0.01

2.2

2.4

1.521

1.521

1.523

1.523

1.531

1.531

Gemmological Tables, Ulrich Henn, 2004 

Gypsum

1.528

1.53

0.009

0.01

2.25

2.35

 

 

 

 

 

 

Gemology Tools Professional 2010

 

CAUSE OF COLOUR

Stone

Colour

Cause of colour

Reference

Gypsum

all colours

colour usually due to dyes exclusively, except for some brown staining due to hydrous iron oxides

Gems & Gemology Summer 1988

 

MINERAL INCLUSIONS

 

LOCALITIES

 

CHEMICAL DATA