Stone

RI min

RI max

Dens min

Dens max

Colour

Location

Info

Spectrum

UVS

UVL

Reference

perublu synthetic opal

1.339

1.35

1.54

1.54

greenish blue

Deutsche Gemmologische Gesellschaft e.V. www.dgemg.co 2016

mexifire synthetic fire opal

1.35

1.35

1.57

1.57

orange

GAAJ-ZENHOKYO Laboratory 2008

mexifire synthetic fire opal

1.38

1.395

1.69

1.74

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2010 Jun, p47-50

mexifire synthetic fire opal

1.38

1.405

1.63

1.77

Brownish orange to orangy yellow

transparent, translucent, snake-like bands under # polariscope

inert

inert

Gems & Gemology 2008 Fall, p228-233

perublu synthetic opal

1.39

1.39

1.75

1.75

electric blue

GAAJ-ZENHOKYO Laboratory 2008

Synthetic opal (Russia)

1.43

1.44

1.94

2.04

white

Scientific Centre for Applied Research, at Dubna, Russia

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2002 Sep, p115-120

Synthetic opal (Russia)

1.44

1.45

1.74

1.86

black opal

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1994 Dez, p107-108

Synthetic opal (Russia)

1.44

1.45

1.74

1.86

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1995 Mar, p9-15

Synthetic opal (Russia)

1.44

1.45

1.75

1.78

white with play of colour

weak to moderate greenish yellow to blue-white

strong bluish white to blue-white

Gems & Gemology 1993 Summer, p139

Synthetic opal (China)

1.45

1.468

1.8

1.9

black opal

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1994 Dez, p108

Synthetic opal (China)

1.45

1.468

1.8

1.9

lizard skin effect, columnar structure

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1995 Mar, p9-15

synthetic fire opal - Inamori

1.459

1.46

1.87

1.91

yellow-orange with play of colour

0.38-2.30 ct

absorption band between 400 and 540nm

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1999 Mar, p37-42

Synthetic opal - Inamori

1.459

1.466

2.2

2.24

colourless, white, black

absence of water, no synthetic, but rather imitation

Gems & Gemology 1987 Fall 1987

Synthetic fire opal

1.46

1.46

1.8

1.8

orange pink, reddish orange, orangy yellow

very strong orangy yellow, evenly distributed

strong yellow, evenly distributed

Gems & Gemology 1999 summer p153

Synthetic opal

1.46

1.47

2.22

2.27

near colourless, white, orange, black; play of colour

by Kyocera (Japan)

semi-transparant; no reaction Chelsea filter; snake skinn pattern and columnar structure

band at 550nm, line at 580nm

white/colourless: very weak to weak chalky blue

Gems & Gemology 2003 Winter, p 340

Synthetic opal - Inamori

1.46

1.46

2.2

2.2

2 cabochons 2.80ct

inert to faint yellowish

Gems & Gemology 1983 Winter, p234-235

Synthetic opal - sterling opal

1.465

1.467

1.72

1.74

white to medium blue with play of colour

hardness 4-5

Gems & Gemology 2012 Spring, p57-58

mexifire synthetic fire opal

1.47

1.47

2.19

2.19

brownish orange to orange brown

inert

inert

Gems & Gemology 2010 winter, p287-290

Synthetic opal (Russia)

1.47

1.47

1.89

1.98

green, red, brown, reddish

Scientific Centre for Applied Research, at Dubna, Russia

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2002 Sep, p115-120

Stone

RI min

RI max

Dens min

Dens max

Reference

Synthetic fire opal - Gilson

1.41

1.41

1.91

1.91

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

synthetic fire opal - Gilson

1.41

1.41

1.91

1.91

Bestimmungstabellen für Edelsteine, Birgit Günther, 2008 

Synthetic opal

1.41

1.47

1.91

2.2

http://www.geminterest.com 

Synthetic opal

1.41

1.45

1.91

2.24

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

Synthetic opal - Gilson

1.41

1.45

1.91

2.24

Joel Arem, Color Encyclopedia of Gemstones, 1987 

Synthetic opal - Gilson

1.41

1.45

2

2.1

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

Synthetic opal - Gilson

1.41

1.45

1.91

2.24

http://www.gemmology.be 

Synthetic opal - Russia

1.43

1.45

1.74

1.86

Bestimmungstabellen für Edelsteine, Birgit Günther, 2008 

Synthetic opal

1.43

1.47

1.97

2.2

Gemology Tools Professional 2010

Synthetic opal

1.437

1.468

1.74

2.28

Gemmo.eu 2013

Synthetic opal

1.44

1.45

1.74

2.07

Gemmological Tables, Ulrich Henn, 2004 

synthetic opal

1.44

1.44

2.3

4.5

Tabellen zur Edelstein-Bestimmung, Pschichholz FGA, 1975 

Synthetic opal

1.44

1.45

1.74

1.86

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

Synthetic opal - Gilson

1.44

1.44

2.05

2.05

Bestimmungstabellen für Edelsteine, Birgit Günther, 2008 

Synthetic opal

1.45

1.468

1.8

1.9

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

Synthetic opal - China

1.45

1.468

1.8

1.9

Bestimmungstabellen für Edelsteine, Birgit Günther, 2008 

synthetic fire opal - Inamori

1.459

1.46

1.87

1.91

Bestimmungstabellen für Edelsteine, Birgit Günther, 2008 

Synthetic opal - Inamori

1.459

1.466

2.2

2.24

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

Synthetic opal

1.46

1.46

2.2

2.2

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

Synthetic opal - Inamori

1.46

1.46

2.2

2.2

http://www.gemmology.be 

Synthetic opal - Inamori

1.46

1.46

2.2

2.24

Bestimmungstabellen für Edelsteine, Birgit Günther, 2008 

Synthetic opal - Inamori

1.463

1.466

2.23

2.24

Bestimmungstabellen für Edelsteine, Birgit Günther, 2008 

Synthetic opal - Russia

1.47

1.47

1.89

1.99

Bestimmungstabellen für Edelsteine, Birgit Günther, 2008