Gemsdat
 

                Home

 

     

INVESTIGATIONS

Stone

RI min

RI max

Dens min

Dens max

Colour

Location

Info

Spectrum

UVS

UVL

Reference

Plastic, artificial product

1.5

1.51

1.2

1.22

milky bluish white, realistic play of colour

 

"opalite", moderate anomalous double refraction, hardness 2.5

general absorption from 537 to 584nm

weak, superficial chalky blue-white overtone

strong even bluish white, very slight orange at the edges

Gems & Gemology 1989 Spring, p30-34

Plastic, artificial product

1.5

1.5

 

 

bright gold to deep brown

 

golden coral imitation

 

inert

inert

Gems & Gemology 2015 Winter, p456

Plastic, artificial product

1.53

 

1.97

1.97

orange-red

 

bead 37.50ct, coral imitation, with coral inclusions

 

orange

orange

Gems & Gemology 2015 Fall, p 341-342

Plastic, artificial product

1.53

 

1.45

1.45

milky bluish white, realistic play of colour

 

"opalite", opal imitation, spot RI

 

 

 

http://gtljaipur.info/ProjectUpload/labDownLoad/LIC%2074%20_June2017.pdf

Plastic, artificial product

1.57

1.57

1.24

1.24

white with striations

 

hardness 2, =polymer substance, with striations imitating Schreger lines

 

inert

inert

Gems & Gemology 2019 Fall, p419

Plastic, artificial product

 

 

1.2

1.2

 

 

trade name "opalus", opal imitation

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1996 Mar, p3

Plastic, artificial product

 

 

 

1.26

 

 

walrus tusk imitation and sperm whale tooth imitation

 

 

 

Gems & Gemology 2003 winter, p 341

 

TABLES

Stone

RI min

RI max

Dens min

Dens max

Reference

Plastics Imitation for coral, amber, pearl, ivory

1.45

1.65

1.15

2.2

Gemmo.eu 

Plastics Imitation for coral, amber, pearl, ivory

1.47

1.7

1.05

1.55

Gemology Tools Professional 2010

Bakelite

1.47

1.47

1.25

2

Gems, R Webster, 5th edition 1994 

"pastoral" plastic

1.48

1.49

1.18

1.2

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

Plastics Imitation for coral, amber, pearl, ivory

1.49

1.7

1.3

1.95

Gemmological Tables, Ulrich Henn, 2004 

Celluloid

1.495

1.52

1.36

1.8

Bestimmungstabellen für Edelsteine, Birgit Günther, 1981 

Celluloid

1.495

1.68

1.04

1.8

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

Celluloid

1.495

1.52

1.25

1.8

http://www.gemmology.be 

Celluloid

1.495

1.51

1.36

1.8

Gems, R Webster, 5th edition 1994 

Celluloid

1.495

1.52

1.25

1.8

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

Perspex - lucite -plastic

1.5

1.5

1.18

1.19

Gems, R Webster, 5th edition 1994 

Bakelite

1.5

1.7

1.25

1.9

Bestimmungstabellen für Edelsteine, Birgit Günther, 1981 

Bakelite

1.5

1.7

1.25

1.35

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

Bakelite

1.5

1.7

1.25

1.29

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

Casein

1.53

1.56

1.32

1.34

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

Polystyrene

1.55

1.56

1.2

1.23

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

Polystyrene

1.55

1.56

1.2

1.23

Bestimmungstabellen für Edelsteine, Birgit Günther, 2008 

Polystyrene

1.55

1.6

1.05

1.23

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

Casein

1.55

1.56

1.32

1.34

Bestimmungstabellen für Edelsteine, Birgit Günther, 1981 

Casein

1.55

1.56

1.33

1.33

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

Casein

1.55

1.56

1.32

1.34

Gems, R Webster, 5th edition 1994 

Polystyrene

1.59

1.59

1.05

1.05

Gems, R Webster, 5th edition 1994 

Bakelite

1.61

1.66

1.25

1.3

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

Bakelite

 

 

1.25

1.3

John Sinkakas, Gemstone and mineral data book,1972 

 

CAUSE OF COLOUR

 

 

CHEMICAL DATA (%)