Stone

RI min

RI max

Dens min

Dens max

Colour

Info

Spectrum

UVS

UVL

Reference

Glass

green

translucent, agate imitation, sold as synthetic agate

DGMG Newsletter 2022 Okt

Glass

1,4

1,4

2,46

2,46

blue

cabochons with unusual star pattern (molded), star sapphire imitation

strong chalky blue

inert

Gems & Gemology 2021 Fall, p261

Glass

1,456

1,456

2,25

2,25

transparent smoky brown

green

green

Gems & Gemology 1976 Spring, p155

Glass

1,46

1,46

2,19

2,2

colourless

spheres sold as rock- crystal balls, spot RI

The Journal of Gemmology 2022 38 (2), p130

Glass

1,47

1,47

2,51

2,51

red

30.12ct, resembles a color-zoned rubellite

strong chalky blue

inert

Gems & Gemology 2008 summer, p186

Glass

1,48

1,48

2,27

2,27

dark greenish blue with pink core

trigonal "crystal", borosilicate glass, resembling tourmaline, tube-like inclusions (= elongated bubbles)

inert

inert

The Journal of Gemmology 2017 Vol35, N°6, p494-496

Glass

1,48

1,48

2,69

2,69

green,

"meta-jade", partly devitrified, 22.69 ct

general absorption below 480 and above 560

weak yellowish green

faint yellowish green

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1993 Dec, p171-177

Glass

1,48

1,48

2,48

2,56

greenish blue

translucent, cabochons 2.17-2.60ct, imitating gem silica

weak greenish white

inert

Gems & Gemology 2020 Summer p314

Glass

1,49

1,49

2,18

2,18

turquoise

0.81 ct bead, turquoise imitation, semi-transparent, impregnated!

Gems & Gemology 2007 Winter, p365

Glass

1,49

1,52

2,48

2,51

electric blue

haüyne simulant, coloured by copper

none

none

In Color 2012 Fall/Winter p42-43

Glass

1,49

1,52

2,492

2,524

turquois, green, blue

with cristalline inclusions, low degree of transparency

Blue stones: Strong greenish yellow and blue; green stones : weak greenish glow

inert or a weaker reaction

GJEPC-India, LAB INFORMATION CIRCULAR 2009 Volume 55 August

Glass

1,5

1,51

2,48

2,52

light blue

partially devitrified imitation of hemimorphite

weak chalky blue, greenish yellow

inert

Gems & Gemology 2012 Summer, p153

Glass

1,5

1,5

2,5

2,5

yellow+blue

imitating blue amber, 139.34ct irregulary shaped

weak chalky blue

inert

Gems & Gemology 2019 Fall, p 444

Glass

1,505

1,505

2,36

2,36

light blue

transparent, 15.55ct, opal imitation

www.dgemg.com 2021 1

Glass

1,506

1,508

2,51

2,56

blue, opaque

imitating lapis lazuli, devitrified glass

The Journal of Gemmology 1987 Vol 20, N°5, p285-286

Glass

1,506

1,508

2,51

2,56

blue

devetrified glass, lapis lazuli imitation, bead 9.53ct and cabochon 5.03ct

The Journal of Gemmology 1987 Vol20, N°5, p285-286

Glass

1,508

1,508

2,453

2,453

violetish blue of strong saturation, opaque to semitranslucent, translucent, to transparent

hardness +/- 5.5

inert

extremely weak

Gems & Gemology 1983 winter, p228-2231

Glass

1,51

1,56

0

0

colourless, blue, green, orange, red

pit glass = prehistoric (?) manmade

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1993 Mar, p27-36

Glass

1,51

1,51

2,45

2,45

violet+yellow

28.98ct, ametrine imitation

yellow part: chalky yellow, violet part: inert

violet part: light yellow, yellow part: inert

The Journal of Gemmology 2018 36(4), p294

Glass

1,514

1,514

2,47

2,47

colourless with opalescence

"slocum stone", imitation opal, H: 5-5.5

inert

inert

Gems & Gemology 1976 Winter, p252-256

Glass

1,516

1,516

2,64

2,64

light grey

cordierite imitation, 15.6ct

The Journal of Gemmology 1977 N°3,p117-118

Glass

1,518

1,521

2,48

2,5

colourless (i.e., water opal simulant), white, black, and blue bodycolors

"mermaid crystal" , opal simulant

moderate to moderately strong yellow

inert

Gems & Gemology 2003 Fall, p239

Glass

1,518

1,53

2,5

2,52

yellowish green to green

represented as natural green obsidian

dark in the blue and in the red

inert, faint yellow, or weak to medium green

inert

Gems & Gemology 1998 Fall, p129

Glass

1,519

1,52

2,47

2,53

green, yellow, blue

trade name : lazerite

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1995 Mar, p8

Glass

1,52

1,52

2,48

2,48

greenish with brown colour zones

imitation of colour zoned quartz

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2014 Dez, p66-68

Glass

1,52

1,52

2,51

2,51

neon blue

6.11ct, haüyne imitation, inclusions of prismatic crystals, copper doped

inert

inert

 GIT-Gem Testing Laboratory 2012 11 July

Glass

1,52

1,52

2,51

2,51

green

3.76 and 3.80ct, moldavite imitation

Gems & Gemology 2016 Winter, p431-433

Glass

1,52

1,52

2,55

2,55

inclusions of synthetic wollastonite crystals and synthetic diopside crystals as divitrification product

Gems & Gemology 2010 summer, p144

Glass

1,52

1,52

2,65

2,65

orangy red

Chinese fiber glass, imitation cat's-eye

Gems & Gemology 2003 Winter, p 339

Glass

1,521

1,521

2,66

2,66

colour change: bluish-green in some fluorescent light (not daylight! Corrected in an erratum), purplish pink in incandescent light

trade-marked as "zandrite"

rear earth spectrum (a lot of lines)

inert

very weak bluish green

Gems & Gemology 2004 spring, p73

Glass

1,524

1,524

2,395

2,395

dark bluish grey in daylight, light yellow in incandescent light

9.57ct

chalky yellow

slight green

Gems & Gemology 2009 Spring

Glass

1,53

1,53

2,31

2,31

green

to imitate emerald

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1992 Sep, p66

Glass

1,53

1,53

2,84

2,84

blue-green

Chinese fiber glass, imitation cat's-eye

Gems & Gemology 2003 Winter, p 339

Glass

1,53

1,53

3,38

3,38

opal imitation

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1989 Dec, p139-142

Glass

1,535

1,535

2,78

2,78

colour change: violet-blue in daylight, purplish pinkin incandescent light

trade name : zandrite

numerous lines and bands across the spectrum

inert

inert

GJEPC-India, LAB INFORMATION CIRCULAR 2009 Volume 53 January

Glass

1,537

1,537

2,64

2,64

bluish purple

moderate band in the yellow at 580 nm

inert

inert

Gems & Gemology 1996 Winter, p270-276

Glass

1,538

1,538

2,82

2,82

colour change: violet-blue in fluorescent light (not daylight!), reddish purple in incandescent light

trade-marked as "zandrite"

rear earth

inert

inert

Gems & Gemology 2005 winter, p364

Glass

1,545

1,545

2,91

2,91

green, colour change to red

1.18ct

inert

inert

ACAM lab  1652

Glass

1,549

1,549

2,75

2,75

colour-changing :yellowish green to brownish pink

diaspor imitation

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2013 62/1-2, Jun, p52

Glass

1,55

1,55

3,09

3,09

reddish orange

spot RI, 2.85ct cabochon, fiber optic glass, cat's-eye

chalky whitish yellow

dull red

Gems & Gemology 1996 Fall, p222

Glass

1,56

1,56

2,99

2,99

"cobalt" blue

Chinese fiber glass, imitation cat's-eye

Gems & Gemology 2003 Winter, p 339

Glass

1,56

1,56

3,11

3,11

light blue

Chinese fiber glass, imitation cat's-eye

Gems & Gemology 2003 Winter, p 339

Glass

1,57

1,57

0

0

irregular layers of green

imitation of malachite, cabochon

inert

white (light green bands)

The Journal of Gemmology 2014 Vol 34, N°4, p 299

Glass

1,57

1,57

3,12

3,12

violetish brown

Chinese fiber glass, imitation cat's-eye

Gems & Gemology 2003 Winter, p 339

Glass

1,57

1,57

3,14

3,14

grey

Chinese fiber glass, imitation cat's-eye

Gems & Gemology 2003 Winter, p 339

Glass

1,57

1,57

3,18

3,18

white

Chinese fiber glass, imitation cat's-eye

Gems & Gemology 2003 Winter, p 339

Glass

1,572

1,572

3,01

3,01

green

imitation of emerald, 4,05ct, fissures in honeycomb-like formation

The Journal of Gemmology 2022 38(1), p24

Glass

1,58

1,58

3,2

3,2

dark green

Chinese fiber glass, imitation cat's-eye

Gems & Gemology 2003 Winter, p 339

Glass

1,58

1,58

3,2

3,2

pink

Chinese fiber glass, imitation cat's-eye

Gems & Gemology 2003 Winter, p 339

Glass

1,6

1,6

2,72

2,72

dark green

Devitrified, resembling actinolite, 12.25 ct

absorption increasing toward both ends of the spectrum, with a transmission window from about 540 to 580 nm

Gems & Gemology 1993 Fall, p201

Glass

1,6

1,6

2,98

2,98

"Swarogreen", emerald imitation, 0.22 carat

greenish-yellow

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1994 Dez, p107

Glass

1,6

1,605

3,36

3,48

blue-violet

"U.M.Tanzanic" tanzanite imitation, 2.89 ct and 0.92 ct

weak absorption bands at approximately 490,550, and 590 nm

chalky white

chalky white

Gems & Gemology 1996 Winter, p270-276

Glass

1,606

1,606

2,99

2,99

mottled brownish green

sphere, opaque, obsidian imitation, numerous spherical inclusions with a silvery metallic luster

no

inert

inert

Gems & Gemology 1998 winter, p 301

Glass

1,608

1,612

2,88

2,94

"Swarogreen", 0.08 to 0.42 ct

strong, broad doublet at about 442 and 448 nm, a triplet at 466, 472, and 483 nm; broad band centered at 590 nm.

weak green

weak to faint yellowish green to greenish yellow

Gems & Gemology 1994 Summer, 130

Glass

1,63

1,63

3,69

3,69

brown

smoky quartz imitation, 19.95ct

strong green-yellow

moderate reddish brown

ACAM lab  4781

Glass

1,635

1,635

3,754

3,754

emerald green

radio-active (up to 0.02 mR/h)

The Journal of Gemmology 1992 Vol23, N°2, p80-82

Glass

1,647

1,647

3,87

3,87

dark blue

Co bands

greyish

inert

ACAM lab  1183

Glass

1,65

1,65

3,87

3,87

pink

10.4ct

bluish

inert

ACAM lab  2096

Glass

1,661

1,661

3,37

3,37

green

aluminosilicate glass

inert

inert

The Journal of Gemmology 2016 35 (3), p 205-206

Glass

1,68

1,69

3,98

4

hessonite imitation, with crystalline inclusions

GJEPC-India, LAB INFORMATION CIRCULAR 2009 Volume 53 January

Glass

1,68

1,68

4,14

4,14

pinkish red

19.41ct

greenish

yellow-green

ACAM lab  1299

Glass

1,681

1,681

4,16

4,16

dark red

27.76ct

greenish

inert

ACAM lab  1372

Glass

1,7

1,7

4,11

4,11

violetish blue

5.42ct, tanzanite imitation

weak bands at 500 and 600 nm

blue

weak blue

Gems & Gemology 2003 Winter, p317-318

Glass

1,705

1,705

4,13

4,13

purplish blue

tanzanite imitation, 8.83ct

no features

weak chalky white

inert

The Journal of Gemmology 2014 Vol 34, No.2, p109-110

Glass

1,71

1,71

4,01

4,01

blue

tanzanite imitation

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2004 Dec, p125

Glass

1,73

1,73

4,36

4,36

green

17.5 ct, emerald imitation

no absorption features

inert

inert

Gems & Gemology 2010 summer, p155-156

Glass

1,74

1,74

3,66

3,66

12ct, tsavorite imitation

general absorption around 500 nm

strong chalky yellow

inert

Gems & Gemology 2003 Summer, p146

Glass

1,745

1,745

4,33

4,33

emerald green

translucent, with crystalline aggregates, 25.04 ct

chalky blue

inert

Gems & Gemology 2010 Winter, p 328-329

Glass

4,43

4,43

greenish brown

peridote imitation, high dispersion

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2004 Dec, p125-126

Glass

4,43

4,43

green

26.82ct, peridot imitation

Gems & Gemology 1999 spring p 44

Glass

4,44

4,44

red, blue, green, yellow, brown, black

hardness 6, RI about 2

Gems & Gemology 1993 winter, p289

Glass

4,65

4,65

green

peridot imitation, high dispersion, barium-zirconium glass, IR > 1.81

inert

inert

Gems & Gemology 2009 Winter, p307-308

Glass

6,58

6,58

intense yellow

IR OTL, 27.73 ct, contains Pb

general absorption from 439

inert

inert

Gems & Gemology 2003 Summer, p147

Glass

4,17

4,17

violet blue

tanzanite imitation, no dispersion, RI > 1.81, cross-like anomalous extinction between crossed polarisers, 14.96ct and 8.04ct

inert

inert

The Journal of Gemmology 2021 Vol37, N)5, p470-472

Stone

RI min

RI max

Dens min

Dens max

Reference

Glass

1.44

1.9

2.3

4.5

Bestimmungstabellen für Edelsteine, Birgit Günther, 1981 

Glass

1.44

1.962

2.3

5.12

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

Glass

1.44

1.77

2.2

4.55

Tabellen zur Edelstein-Bestimmung, Pschichholz FGA, 1975 

Glass

1.44

1.9

2.3

4.5

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

Glass

1.44

1.7

2.08

4.3

Gemmo.eu 2013

Glass

1.47

1.7

2.3

4.5

Gemology Tools Professional 2010

Glass

1.48

1.7

2.39

4

Gemmological Tables, Ulrich Henn, 2004 

Glass

1.7

2.1

4.3

5

Gemmo.eu 2013

Stone

Colour

Cause of colour

Reference

Glass (Chinese fiber)

black, green, yellow, orange, brown, blue

Black was associated with traces of Mn; green with Cu, Cr, and/or Fe; yellow to orange to brown with Fe; and bright blue with Co.

Gems & Gemology 2003 winter, p340

Inclusion

Stone

Reference

wollastonite

glass

Gems & Gemology Winter 2017, p470

diopside

glass

Gems & Gemology Winter 2017, p470

Stone

Colour

Made in

Reference

SiO2

Al2O3

MnO

MgO

TiO2

CaO

Na2O

Cr2O3

ZnO

Fe2O3

K2O

CuO

H2O

CoO

P2O5

PbO

ZrO2

BaO

As2O3

Glass

olive standard; industriel

The Journal of Gemmology 2000, Vol 27, N°5,p282

71.68

1.96

0.01

2.88

0.05

10.1

12.44

0.1

0.51

Glass

brown standard; industriel

The Journal of Gemmology 2000, Vol 27, N°5,p282

69.65

2.15

0.03

3.03

0.05

9.73

13.64

0.3

1.35

Glass

green standard; industriel

The Journal of Gemmology 2000, Vol 27, N°5,p282

71.57

1.65

0.22

2.12

0.06

10.29

12.71

0.33

0.67

Glass

blue (chalcedony imitation)

Taiwan

The Journal of Gemmology 2000, Vol 27, N°5,p282

72.97

0.45

3.86

0.02

9.13

13.09

0.01

0.17

0.31

Glass

dark brown standard; industriel

The Journal of Gemmology 2000, Vol 27, N°5,p282

78.02

Glass

blue (chalcedony imitation)

Taiwan

The Journal of Gemmology 2000, Vol 27, N°5,p282

73.3

0.34

3.85

0.02

9.11

12.98

0.01

0.14

0.26

Glass

blue (chalcedony imitation)

Taiwan

The Journal of Gemmology 2000, Vol 27, N°5,p282

73.01

0.33

3.86

0.02

8.54

13.83

0.01

0.14

0.26

Glass

colourless, slightly greenish

"pit glass"

Sri Lanka

Zeitschrift der deutschen gemmologischen Gesellschaft, 1993, Mar, p31

68.9

1.7

0.02

2.06

0.03

12.5

11.9

0.3

0.2

0.86

0.1

0.03

0.34

0.1

0.02

0.05

Glass

cobalt blue

"pit glass"

Sri Lanka

Zeitschrift der deutschen gemmologischen Gesellschaft, 1993, Mar, p31

69.1

2.6

0.06

0.02

0.05

7.7

14.3

3.2

0.06

0.91

0.6

0.15

0.07

0.05

0.03

0.002

0.3

Glass

emerald green

"pit glass"

Sri Lanka

Zeitschrift der deutschen gemmologischen Gesellschaft, 1993, Mar, p31

67.6

2.8

0.02

0.02

0.01

11.5

13.6

0.2

0.03

0.07

2.07

0.14

0.16

0.07

0.04

0.005

0.4

Glass

light blue

"pit glass"

Sri Lanka

Zeitschrift der deutschen gemmologischen Gesellschaft, 1993, Mar, p31

58.4

15

0.2

0.05

0.2

1.3

9.16

0.09

0.2

1.28

0.25

0.56

0.11

11.2

0.1

0.65

Glass

orange

"pit glass"

Sri Lanka

Zeitschrift der deutschen gemmologischen Gesellschaft, 1993, Mar, p31

70.1

1.6

0.09

0.04

0.03

10.1

10.88

0.12

0.06

4.99

0.06

0.34

0.08

0.16

0.01

0.3

Glass

red

"pit glass"

Sri Lanka

Zeitschrift der deutschen gemmologischen Gesellschaft, 1993, Mar, p31

53.4

2

0.18

0.02

0.006

0.8

14.8

0.06

0.12

0.22

0.07

1.26

0.22

26.2

0.5

Glass

"slocum stone"

Gems & Gemology 1976, Winter, p256

72.5

0.51

4.32

8.29

13.65

0.31