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INVESTIGATIONS

Stone

RI min

RI max

Biref min

Biref max

Dens min

Dens max

Colour

Location

Info

ne min

ne max

no min

no max

Spectrum

UVS

UVL

Reference

Dravite

1.611

1.64

0.025

0.025

2.995

3.022

dark brown

Jajarkot, Nepal

 

1.611

1.615

1.636

1.640

 

 

 

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1993 Sep, p73

Dravite

1.612

1.632

0.02

0.02

3.02

3.02

orangy yellow

Cabo Delgado Province, Mozambique

1.67ct

 

 

 

 

weak band at 500 nm

weak yellow

inert

Gems & Gemology 2007 Spring, p74

Dravite

1.62

1.64

0.02

0.02

3.04

3.06

dark brownish green to dark grayish green

Cabo Delgado Province, Mozambique

2.43 - 4.37 ct

 

 

 

 

absorption band at 500 nm

inert

inert

Gems & Gemology 2007 Spring, p74

Dravite

1.62

1.639

0.019

0.019

 

 

slightly orangey yellow

Tanzania

11.13ct

 

 

 

 

 

 

 

The Journal of Gemmology 2016 35 (3), p 190-192

Dravite

1.619

1.637

0.018

0.018

3.06

3.06

dark yellowish green

Taita Hills, Taita-Taveta district), Coast Province, Kenya

13.31ct

 

 

 

 

broad absorption below 420nm and above 680nm

inert

weak yellow

GIA Gem Database  35039

Dravite

1.62

1.638

0.018

0.018

3.04

3.04

dark yellowish orange

Mozambique

31.21ct

 

 

 

 

broad absorption below 440nm and from 500-540nm, lines at 450, 459, 538nm

inert

inert

GIA Gem Database  33635

Dravite

1.622

1.646

0.02

0.023

 

 

yellow

Yellow Mine, Kenya

solide solutions between dravite and uvite 78-22 to 90-10

1.622

1.624

1.643

1.646

 

 

 

The Journal of Gemmology 2000 Vol 27, N°1, p11-29

Dravite

1.623

1.64

0.017

0.017

2.922

2.922

 

Elahera, Sri Lanka

 

1.623

1.623

1.640

1.640

 

 

 

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1985 34, Nr3/4, p98-100

Dravite

1.624

1.654

0.03

0.03

3.03

3.07

red to brownish red, transparent

Zambia

 

 

 

 

 

band 520-590nm, weaker band 460-470nm, cutoff of the blue (440)

 

 

Gems & Gemology 1985 spring p35-39

Elbaite

1.616

1.63

0.014

0.014

3.02

3.02

red-purple

Conselheiro Pena, Minas Gerais, Brazil

13.27ct

 

 

 

 

broad absorption below 420nm and from 510-560nm; line at 450nm

inert

inert

GIA Gem Database  34310

Elbaite

1.618

1.642

0.02

0.02

3.04

3.1

green

Virunga Region, Kivu, Congo

 

1.618

1.622

1.638

1.642

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2010 59/3-4, p111-113

Elbaite

1.618

1.638

0.02

0.02

3.07

3.07

blue and red-orange

Karibib, Erongo Region, Namibia

5.57ct

 

 

 

 

red-orange: broad absorption below 420nm and above 680nm, line at 450nm

inert

inert

GIA Gem Database  34239

Elbaite

1.619

1.639

0.018

0.019

3.05

3.08

pink

Luc Yen, Vietnam

 

1.619

1.621

1.638

1.639

 

inert

inert

Gems & Gemology 2012 Fall, p169

Elbaite

1.62

1.649

0.017

0.024

2.989

3.143

green, pink, brownish green, brown

Hyakule, Nepal

 

1.620

1.627

1.638

1.649

 

 

 

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1993 Sep, p73

Elbaite

1.62

1.646

0.02

0.023

3.065

3.097

yellow, yellow-brown

Naje, Nepal

 

1.620

1.623

1.640

1.646

 

 

 

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1993 Sep, p73

Elbaite

1.62

1.64

0.02

0.02

3.16

3.16

very dark red

Teofilo Otoni, Minas Gerais, Brazil

8.01ct

 

 

 

 

broad absorption below 450nm and from 520-570nm

inert

inert

GIA Gem Database  33606

Elbaite

1.62

1.64

0.02

0.02

3.04

3.04

yellowish orange

Embu, Eastern Province, Kenya

3.36ct

 

 

 

 

broad absorption below 430nm and above 670nm

inert

medium orange-yellow

GIA Gem Database  34379

Elbaite

1.62

1.637

0.017

0.017

3.05

3.05

yellow-green and yellow

Nacala, Nampula Province, Mozambique

31.48ct

 

 

 

 

broad absorption below 430nm

inert

inert

GIA Gem Database  34229

Elbaite

1.62

1.64

0.02

0.02

2.95

2.95

green

Neu Schwaben Mine, Karibib, Erongo Region, Namibia

10.00ct

 

 

 

 

broad absorption below 420nm and above 650nm, line at 497nm

inert

inert

GIA Gem Database  34726

Elbaite

1.62

1.642

0.022

0.022

3.11

3.11

yellow

Manang, Gandaki Zone, Western Region, Nepal

3.61ct

 

 

 

 

broad absorption below 430nm

inert

inert

GIA Gem Database  34750

Elbaite

1.62

1.639

0.019

0.019

3.08

3.08

bluish green

Nursitan Province, Afghanistan

12.13ct

 

 

 

 

broad absorption below 420nm and above 670nm, lines at 459, 498nm

inert

inert

GIA Gem Database  33658

Elbaite

1.621

1.639

0.018

0.018

3.08

3.08

colourless

Pala, San Diego County, California, USA

4.80ct

 

 

 

 

 

inert

inert

GIA Gem Database  33591

Elbaite

1.621

1.64

0.019

0.019

3.07

3.07

light red

Stewart Lithia Mine, Pala, San Diego County, California, USA

16.84ct

 

 

 

 

broad absorption below 420nm

inert

inert

GIA Gem Database  33588

Elbaite

1.621

1.64

0.017

0.019

3.17

3.2

green

Luc Yen, Vietnam

 

1.621

1.625

1.635

1.640

 

inert

inert

Gems & Gemology 2012 Fall, p169

Elbaite

1.622

1.64

0.018

0.018

3.06

3.06

green

Nursitan Province, Afghanistan

 

 

 

 

 

 

inert

inert

GIA Gem Database  33648

Elbaite

1.622

1.639

0.017

0.017

3.04

3.04

yellowish orange

Alto Ligonha, Zambezia Province, Mozambique

7.50ct

 

 

 

 

broad absorption below 420nm

inert

inert

GIA Gem Database  34531

Elbaite

1.622

1.64

0.016

0.016

3.2

3.2

greenish yellow

Nacala, Nampula Province, Mozambique

16.08ct

 

 

 

 

broad absorption below 430nm and above 670nm

inert

inert

GIA Gem Database  34526

Elbaite

1.622

1.64

0.018

0.018

3.05

3.05

orangy yellow and green-yellow

Nacala, Nampula Province, Mozambique

48.86ct

 

 

 

 

broad absorption below 420nm and above 670nm, lines at 450, 538nm

inert

inert

GIA Gem Database  34492

Elbaite

1.622

1.64

0.018

0.018

3.12

3.12

red-purple and orangy red

Stewart Lithia Mine, Pala, San Diego County, California, USA

4.88ct

 

 

 

 

red-purple : broad absorption below 420nm, from 500-540nm and above 680nm

inert

inert

GIA Gem Database  34245

Elbaite

1.622

1.64

0.018

0.018

3.05

3.05

colourless

Brazil

40.08ct

 

 

 

 

 

inert

inert

GIA Gem Database  33585

Elbaite

1.622

1.642

0.02

0.02

3.2

3.2

bluish green

Neu Schwaben Mine, Karibib, Erongo Region, Namibia

9.19ct

 

 

 

 

broad absorption below 420nm and above 650nm, line at 497nm

inert

inert

GIA Gem Database  34728

Elbaite

1.622

1.64

0.018

0.018

3.04

3.04

purplish red

Alto Ligonha, Zambezia Province, Mozambique

11.41ct

 

 

 

 

broad absorption below 420nm and between 500-540nm, lines at 450, 459, 538nm

inert

inert

GIA Gem Database  34500

Elbaite

1.623

1.64

0.017

0.017

3.02

3.02

yellow

Minas Gerais, Brazil

7.23ct

 

 

 

 

broad absorption below 420nm

inert

inert

GIA Gem Database  33617

Elbaite

1.623

1.639

0.016

0.016

3.04

3.04

dark orange

Alto Ligonha, Zambezia Province, Mozambique

7.13ct

 

 

 

 

broad absorption below 420nm and between 500-540nm, lines at 450, 459, 538nm

inert

inert

GIA Gem Database  34507

Elbaite

1.623

1.64

0.017

0.017

3.06

3.06

yellowish orange

Nacala, Nampula Province, Mozambique

8.05ct

 

 

 

 

 

inert

inert

GIA Gem Database  33612

Elbaite

1.623

1.642

0.019

0.019

3.24

3.24

greenish blue

Alto Ligonha, Zambezia Province, Mozambique

12.87ct

 

 

 

 

broad absorption above 660nm, line at 497nm

inert

inert

GIA Gem Database  34524

Elbaite

1.624

1.644

0.02

0.02

3.11

3.11

violetish purple

Anjanabonoina Mine, Ambohimanambola, Antananarivo Province, Madagascar

6.53ct

 

 

 

 

broad absorption above 680nm

inert

inert

GIA Gem Database  33624

Elbaite

1.624

1.645

0.021

0.021

3.11

3.11

yellow

Manang, Gandaki Zone, Western Region, Nepal

5.50ct

 

 

 

 

broad absorption below 440nm

inert

inert

GIA Gem Database  34749

Elbaite

1.624

1.644

0.02

0.02

3.17

3.17

dark greenish blue

Neu Schwaben Mine, Karibib, Erongo Region, Namibia

3.88ct

 

 

 

 

broad absorption below 420nm and above 640nm, line at 498nm

inert

inert

GIA Gem Database  33679

Elbaite

1.624

1.644

0.016

0.02

3.06

3.08

reddish brown

Luc Yen, Vietnam

 

1.624

1.626

1.638

1.644

 

inert

inert

Gems & Gemology 2012 Fall, p169

Elbaite

1.625

1.641

0.016

0.016

3.05

3.05

purplish red

Itinga, Minas Gerais, Brazil

16.87ct

 

 

 

 

broad absorption below 420nm and from 510-560nm; line at 450nm

inert

inert

GIA Gem Database  34309

Elbaite

1.625

1.643

0.018

0.018

3.16

3.16

blue and red-purple

Neu Schwaben Mine, Karibib, Erongo Region, Namibia

9.88ct

 

 

 

 

blue : broad absorption below 420nm and above 650nm; red-purple : broad absorption below 430nm and above 670nm

inert

inert

GIA Gem Database  34729

Elbaite

1.625

1.646

0.017

0.018

3.17

3.19

yellow

Luc Yen, Vietnam

 

1.625

1.628

1.642

1.646

 

inert

inert

Gems & Gemology 2012 Fall, p169

Elbaite

1.626

1.642

0.016

0.016

3.13

3.13

green-blue

Mursinka, Ural Mts, Russia

1.80ct

 

 

 

 

broad absorption below 420nm and above 670nm; lines at 459, 498nm

inert

inert

GIA Gem Database  33671

Elbaite

1.628

1.646

0.018

0.018

3.05

3.05

red-purple

Governador Valadares, Minas Gerais, Brazil

4.52ct

 

 

 

 

broad absorption below 420nm and from 510-540nm, line at 455nm

inert

inert

GIA Gem Database  33604

Elbaite

1.628

1.642

0.014

0.014

3.05

3.05

purplish red and yellowish green

Itambacuri, Minas Gerais, Brazil

20.15ct

 

 

 

 

broad absorption below 420nm ; lines at 450, 459nm

inert

inert

GIA Gem Database  34311

Elbaite

1.628

1.646

0.018

0.018

3.09

3.09

orange

Voi, Taita-Taveta district, Coast Province, Kenya

3.68ct

 

 

 

 

broad absorption below 430nm

inert

inert

GIA Gem Database  33624

Elbaite

1.628

1.646

0.018

0.018

3.17

3.17

bluish green

Usakos, Karibib District, Erongo Region, Namibia

6.02ct

 

 

 

 

broad absorption below 420nm and above 670nm, line at 498nm

inert

inert

GIA Gem Database  33665

Elbaite

1.629

1.643

0.014

0.014

3.13

3.13

greenish blue

Neu Schwaben Mine, Karibib, Erongo Region, Namibia

7.25ct

 

 

 

 

broad absorption above 680nm, line at 420nm

inert

inert

GIA Gem Database  33672

Elbaite

1.63

1.65

0.02

0.02

3.18

3.18

yellow

Chipata, Eastern Province, Zambia

8.37ct

 

 

 

 

broad absorption below 440nm

inert

inert

GIA Gem Database  33619

Elbaite

1.619

1.641

0.02

0.02

3.04

3.07

yellowish green to light to dark green, pinkish green, pink, pinkish red, pink-violet

Rwanda

 

1.619

1.621

1.639

1.641

 

 

 

The Journal of Gemmology 2014 Vol 34, N°4, p 344-349

Elbaite - Cu-bearing

1.615

1.644

0.018

0.021

3.05

3.11

light green, yellow, gold yellow, greyish blue, greyish violet, orange-red, colour-change: amethyst-coloured to blue under incandescent light

Paraiba, Brazil

 

1.615

1.626

1.635

1.644

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2003 Mar, p25-30

Elbaite - Cu-bearing

1.615

1.64

0.017

0.02

3.04

3.07

bright blue

Salgadinho, Paraiba, Brazil

 

1.615

1.620

1.632

1.640

 

 

 

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1990 Apr, p3-11

Elbaite - Cu-bearing

1.618

1.642

 

 

3.01

3.05

pink, zoned yellow and pink,  zoned greenish yellow and pink

Akwandoka, Keffi, Nigeria

New find 2008

 

 

 

 

 

moderate chalky blue

inert

Gems & Gemology 2009 Fall, p227-228

Elbaite - Cu-bearing

1.618

1.642

0.018

0.021

3.04

3.13

green, blue, violet-blue

Brazil (Batalha, Mulungu and Alto dos Quintos), Nigeria (Edeko), Mozambique (Alto Ligonha)

 

1.618

1.621

1.638

1.642

 

 

 

Gems & Gemology 2006 Spring p4-21

Elbaite - Cu-bearing

1.618

1.64

0.018

0.021

3.06

3.1

green, violet, blue

Glorious mine, Junco do Serido, Paraiba, Brazil

 

1.618

1.620

1.638

1.640

 

inert

inert

Gems & Gemology 2007 fall, p236

Elbaite - Cu-bearing

1.618

1.64

0.019

0.02

3.04

3.05

green, green-blue, pink to red

Mozambique

 

1.618

1.620

1.637

1.640

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1997 Mar, p50-52

Elbaite - Cu-bearing

1.618

1.64

0.018

0.02

3.04

3.09

violet, pink, purple, blue, greenish blue, yellowish green, green, bicoloured, tricoloured

Mozambique

 

1.618

1.620

1.638

1.640

 

inert

inert

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2006 Jun, p5-24

Elbaite - Cu-bearing

1.618

1.639

0.019

0.021

3.08

3.1

 

Mulungu mine, Rio Grande do Norte, Brazil

 

1.618

1.619

1.638

1.639

 

inert

inert

Gems & Gemology 2001 winter p270

Elbaite - Cu-bearing

1.618

1.64

0.02

0.02

3.04

3.08

violet, blue, blue-green, bluish violet, reddish violet

Nigeria

 

1.618

1.620

1.638

1.640

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2001 Dec, p217-223

Elbaite - Cu-bearing

1.618

1.64

0.018

0.02

3.04

3.1

bright blue, green, greenish-blue

Quintos de Baixo, Rio Grande do Norte, Brazil

60 ex

1.618

1.620

1.638

1.640

 

inert

inert

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2005 Sep, p73-84

Elbaite - Cu-bearing

1.618

1.646

0.018

0.025

3.03

3.12

yellowish green, greenish grey, purple-pink, purple, bluish purple, blue, violetish blue, bluish green, turquoise, green

Sao José da Batalha, Paraiba, Brazil

 

1.618

1.621

1.638

1.646

 

inert

inert

Gems & Gemology 1990 fall, p189-205

Elbaite - Cu-bearing

1.619

1.643

0.018

0.021

3.01

3.09

violet, purple, green, blue,

Mavuco, Mozambique

 

1.619

1.622

1.638

1.643

 

 

 

Gems & Gemology 2008 spring p 5-30

Elbaite - Cu-bearing

1.619

1.646

0.018

0.025

3.03

3.12

 

Mina da Batalha, Paraiba, Brazil

 

1.619

1.621

1.638

1.646

 

inert

inert

Gems & Gemology 2001 winter p270

Elbaite - Cu-bearing

1.619

1.64

0.018

0.02

3.04

3.08

 

Mt Mica, Maine, USA

 

1.619

1.622

1.638

1.640

 

inert

inert

Gems & Gemology 2005 summer, p150-163

Elbaite - Cu-bearing

1.62

1.64

0.018

0.018

3.05

3.2

pink, green, purple, brown, orange, black, red

Momeik (Molo) , Mogok, Birma

 

 

 

 

 

 

inert and weak yellow

inert and weak yellow

The Australian Gemmologist 2005 22, p303-309

Elbaite - Cu-bearing

1.62

1.638

0.018

0.019

3.06

3.07

light to medium greenish blue

Nigeria

 

1.636

1.638

1.618

1.620

cutoff at 650nm

inert

inert

Gems & Gemology 2002 spring, p99

Elbaite - Cu-bearing

1.62

1.648

0.019

0.022

 

 

gree, emerald green, light blue, blue-violet

Salgadinho, Paraiba, Brazil

 

1.620

1.626

1.640

1.648

 

 

 

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1990 Sep, p165-167

Elbaite - Cu-bearing

1.62

1.643

 

 

3.01

3.12

highly saturated violet to bluish violet, blue, bluish green, green and purple

Nigeria

0.31 - 1.04 ct

 

 

 

 

 

inert

inert

Gems & Gemology 2007 Winter, p384

Elbaite - Cu-bearing

1.621

1.64

0.018

0.019

3.05

3.06

color change from purple in daylight to grey bluish green in incandescent light

Mozambique

 

1.621

1.621

1.639

1.640

 

inert

inert

Gems & Gemology 2004 Fall, p251

Elbaite - Cu-bearing

1.622

1.644

0.02

0.02

2.99

2.99

greyish green

Sao José da Batalha, Paraiba, Brazil

 

1.622

1.624

1.642

1.644

 

 

 

Gems & Gemology 1994 fall p178-183

Elbaite - Cu-bearing

1.624

1.646

0.022

0.022

3.03

3.03

 

Alto dos Quintos mine, Rio Grande do Norte, Brazil

 

 

 

 

 

 

 

 

Gems & Gemology 2001 winter p270

Elbaite - Cu-bearing

 

 

 

 

 

 

commonly colour zoned, with an "electric" blue rim and a pink-to-violet interior

Mineraçao Batalha Mine, Paraiba, Brazil

 

 

 

 

 

 

 

 

Gems & Gemology 2007 fall, p238

Liddicoatite

1.619

1.651

0.014

0.027

3.05

3.11

red, violetish red, pink, pinkish yellow, colourless, violet, green, brown, pale blue, yellow

Anjanabonoina, Madagascar

liddicoatite-elbaite, transparent to translucent

1.619

1.634

1.635

1.651

 

inert to moderate greenish yellow to golden yellow

inert

Gems & Gemology 2002 Spring p28-53

Liddicoatite

1.62

1.64

0.02

0.02

3.06

3.06

light brownish green to dark greenish brown

 

 

 

 

 

 

weak band at 500nm

inert

inert

Gems & Gemology 2007 spring p74

Liddicoatite

1.621

1.639

0.018

0.018

3.07

3.08

reddish purple

Nigeria

 

 

 

 

 

 

inert to very weak greenish yellow

inert

Gems & Gemology 2001 fall p240

Liddicoatite

1.621

1.641

0.018

0.02

3.06

3.08

greenish blue

Mozambique?

1.29-1.45ct

1.621

1.622

1.640

1.641

 

 

 

Gems & Gemology 2010 winter, p323-325

Mn-rich tourmaline

1.62

1.641

0.021

0.021

3.1

3.1

Canary yellow

Malawi

2ea

 

 

 

 

none

inert

inert

Gems & Gemology 2001 summer p151-152

Mn-rich tourmaline

1.623

1.649

0.02

0.025

3.11

3.17

yellow, brownish yellow, yellowish green

Canary mining area, eastern Province, Zambia

°first large pocket mids 1990, =elbaite

1.623

1.625

1.645

1.649

absorption to 460nm

inert

inert

Gems & Gemology 2007 winter , p314-331

Tourmaline

1.61

1.638

0.02

0.021

 

 

green, color-zoned

Makuki, Kenya

usumbara effect, Cr- and V-bearing

1.610

1.617

1.630

1.638

 

 

 

The Journal of Gemmology 2015 Vol 34, No.6, p476-477

Tourmaline

1.615

1.638

0.023

0.023

3.09

3.09

greenish brown

Sri Lanka

2.1ct

 

 

 

 

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1998 Sep, p169

Tourmaline

1.615

1.633

0.018

0.018

3.02

3.02

colourless

Afghanistan

 

 

 

 

 

 

 

 

The Journal of Gemmology 1974 N°4, p173-174

Tourmaline

1.617

1.637

0.02

0.02

 

 

greenish blue

Landanai, Tanzania

 

 

 

 

 

 

 

 

Revue de  Gemmologie A.F.G. 2006 n°157, p4-7

Tourmaline

1.618

1.638

0.018

0.02

3.04

3.07

greenish brown, dark green

Elahera, Sri Lanka

 

 

 

 

 

cut-off 530nm

inert

inert

Gems & Gemology 1986 Summer, p91

Tourmaline

1.618

1.64

0.02

0.02

3.04

3.07

yellowish brown to brown

Tunduru-Songea region, Tanzania

dravite and uvite

1.618

1.620

1.638

1.640

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1997 Mar, p39-41

Tourmaline

1.619

1.65

0.02

0.023

3.04

3.05

greenish yellow or yellow to brownish yellow

Kenya

=dravite-uvite

1.619

1.630

1.642

1.650

 

 

 

Gems & Gemology 2007 winter , p324

Tourmaline

1.619

1.639

0.014

0.02

3.04

3.055

purplish pink to red purple to orangy red, yellowish green to greenish yellow, pink and yellowish green, multicoloured

Lundazi, Zambia

 

1.619

1.620

1.637

1.639

 

inert

inert

Gems & Gemology 1997 Fall, p204-211

Tourmaline

1.619

1.642

0.018

0.02

3.04

3.07

red

Nigeria

 

1.619

1.622

1.637

1.642

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2001 Dec, p225-228

Tourmaline

1.619

1.641

0.014

0.02

3.04

3.09

green, yellow-green, greenish-blue, pink, purplish-red

Dunton Gem Quarry, Newry, Oxford County, Maine

 

1.619

1.621

1.634

1.641

 

faint to moderate chalky blue

 

Gems & Gemology 1975 Spring, p19-24

Tourmaline

1.619

1.637

0.018

0.018

0

0

light pink

Nepal

5.48ct

 

 

 

 

 

moderate chalky violetish blue

very slight suggestion of a blue

Gems & Gemology 1988 Spring, p51-52

Tourmaline

1.619

1.64

0.021

0.021

3.18

3.18

very strongly greenish-blue

 

1.21ct

 

 

 

 

 

inert

inert

http://www.spec4gem.info/index.php 2016

Tourmaline

1.619

1.642

0.022

0.022

3.044

3.044

golden yellow

Kenya

dravite-uvite ratio 80:20

 

 

 

 

 

medium strong yellow

inert

The Journal of Gemmology 1981 N°7 p437-442

Tourmaline

1.62

1.64

0.019

0.02

2.88

3.09

pale to dark green, usually with a yellowish or, less commonly wuith a bluish tint

Dudley pegmatite, Kangaroo Island, Australia

 

 

 

 

 

 

inert

inert

The Australian Gemmologist 1988 Nov,p 455-458

Tourmaline

1.62

1.648

0.02

0.024

3.05

3.1

green,  yellow, red, brown, pink, yellow-green

Jagoda, Zambia

 

1.620

1.624

1.640

1.648

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2000 Mar, p31-48

Tourmaline

1.62

1.64

0.02

0.02

3.06

3.06

orange

Nigeria

6.72 ct

1.620

1.620

1.640

1.640

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2000 Jun 2000, p62

Tourmaline

1.62

1.64

0.02

0.02

3.04

3.04

red

Vietnam

7.21 ct

 

 

 

 

strong absorption band at 535nm

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1999 Sep, p121-122

Tourmaline

1.62

1.646

0.02

0.026

3.06

3.14

green to bluish green, blue

Coolgardie, Western Australia

 

1.620

1.622

1.640

1.646

strong band around 490 nm

inert

inert

The Australian Gemmologist 2011 Jul-Sep, p171-175

Tourmaline

1.62

1.64

0.02

0.02

3.05

3.05

red or pink, bicoloured green and pink

Nigeria

 

 

 

 

 

 

 

 

Gems & Gemology 1998 winter, p 298-299

Tourmaline

1.62

1.64

0.02

0.02

3.11

3.11

greyish blue

Orissa, India

1.74 ct

 

 

 

 

 

 

 

Gems & Gemology 1993 Summer, p133

Tourmaline

1.62

1.64

0.02

0.02

3.07

3.07

dark violetish blue

Paraiba, Brazil

15.18ct

 

 

 

 

 

inert

inert

Gems & Gemology 1989 Winter, p241-242

Tourmaline

1.621

1.64

0.019

0.019

3.07

3.07

green, blue, blue-green

Neu-Schwaben, Namibia

elbaite-schorl with aditional tsilaite component in blue and blue-green samples

 

 

 

 

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1999 Mar, p2

Tourmaline

1.621

1.649

0.028

0.028

3.13

3.13

yellowish green

 

38.47ct

 

 

 

 

a cut-off at about 410 nin, a
strong absorption band from 418 to 420 nm, and a fainternarrow band at 423.5nm

inert

inert

Gems & Gemology 1986 Fall, p 175-176

Tourmaline

1.622

1.64

0.018

0.018

3.06

3.06

pink to red

Nigeria

 

 

 

 

 

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1998 Dec, p179

Tourmaline

1.622

1.64

0.018

0.018

3.03

3.03

colourless

Sri Lanka

2.96ct

 

 

 

 

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1999 Jul p106

Tourmaline

1.622

1.644

0.022

0.022

3.06

3.06

green (red)

Umba Valley, Tanzania

usambara effect, chelsea : red

 

 

 

 

Cr

mustard yellow

 

The Journal of Gemmology 1997 Vol 25, N°5, p325-330

Tourmaline

1.623

1.645

0.022

0.022

3.09

3.09

yellow

Nigeria

elbaite-tsilaisite serie

1.623

1.623

1.645

1.645

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2000 Jun 2000, p61

Tourmaline

1.628

1.648

0.02

0.02

 

 

bruingeel

South Kenya

 

 

 

 

 

 

 

 

Revue de  Gemmologie A.F.G. 2006 n°157, p4-7

Tourmaline

1.63

1.65

0.02

0.02

3.05

3.05

brownish orangy yellow, with some green areas

Kenya

"savannah" or "golden" tourmaline

 

 

 

 

general absorption to about 480 nm

moderately chalky, moderately strong yellow

inert

Gems & Gemology 1996 Summer, p135-136

Tourmaline

 

 

 

 

 

 

 

Umba Valley, Tanzania

Usambara effect

 

 

 

 

 

 

 

The Journal of Gemmology 1999 Vol 26, N° 6, p386-396

Tourmaline colour change

1.622

1.645

0.022

0.023

3.04

3.06

green, colour change brownish red in artificial light

East Africa

 

1.644

1.645

1.622

1.622

 

 

 

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1988 36, Nr 3/4,p161

trapiche tourmaline

1.62

1.64

0.02

0.02

2.82

2.99

green, black carbonaceous  inclusion material responsible for trapiche pattern is concentrated in elongate growth channels

Kavungu Mine, Jivunda, Chief Sailunga's area, Zambia

 

 

 

 

 

 

weak to moderate chalky yellow

inert

Gems & Gemology 2007 Spring p36-46

Uvite

1.61

1.628

0.018

0.018

3.04

3.04

green

Brumado, Brazil

chelsea : red

 

 

 

 

Cr lines difficult to discern

 

 

The Journal of Gemmology 1998 Vol 26, N°4, p232

Uvite

1.619

1.648

0.016

0.021

2.85

3.244

brown

Elahera, Sri Lanka

 

1.619

1.631

1.635

1.648

 

 

 

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1985 34, Nr3/4, p98-100

Uvite

1.62

1.641

0.021

0.021

2.99

3.04

brownish orange

Kunar Province, Afghanistan

0.59 and 1.46 ct

 

 

 

 

 

chalky greenish orange

inert

Gems & Gemology 2002 Winter, p357-358

Uvite

1.622

1.643

0.019

0.021

3.05

3.07

brownish orange, brown yellow, orangy-yellow, brownish yellowish green, yellowish green, bicoloured  yellow-green and reddish brown

Morogoro, Tanzania

transparent, in fact = uvite-dravite tourmaline; chelsea none to medium red

1.622

1.623

1.641

1.643

 

weak to strong chalky greenish yellow

inert

Gems & Gemology 2006 summer, p182-184

 

TABLES

Stone

RI min

RI max

Biref min

Biref max

Dens min

Dens max

ne min

ne max

no min

no max

Reference

Buergerite

1.653

1.737

0.07

0.084

3.25

3.35

 

 

 

 

Gemmo.eu 2013

Buergerite

1.655

1.735

0.065

0.08

3.29

3.32

 

 

 

 

http://www.gemmology.be 

Buergerite

1.655

1.735

0.065

0.08

3.29

3.32

1.655

1.670

1.735

1.735

http://www.geminterest.com 

Buergerite

1.655

1.735

0.065

0.08

3.29

3.32

 

 

 

 

Gemology Tools Professional 2010

Chromdravite

1.772

1.778

0.006

0.006

3.39

3.41

 

 

 

 

http://www.gemmology.be 

Cr-Tourmaline

1.622

1.643

0.019

0.021

3.05

3.07

1.622

1.623

1.641

1.643

http://www.geminterest.com 

Cr-Tourmaline

1.772

1.778

0.006

0.006

3.39

3.41

1.772

1.772

1.778

1.778

Joel Arem, Color Encyclopedia of Gemstones, 1987 

Cr-Tourmaline

1.772

1.778

0.006

0.006

3.39

3.41

1.772

1.772

1.778

1.778

http://www.geminterest.com 

Cr-Tourmaline

1.772

1.778

0.006

0.006

3.39

3.41

 

 

 

 

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

Cr-Tourmaline

1.772

1.778

0.006

0.006

3.39

3.41

 

 

 

 

Gemology Tools Professional 2010

Dravite

1.604

1.675

0.016

0.032

2.9

3.29

 

 

 

 

http://www.gemmology.be 

Dravite

1.604

1.675

0.016

0.032

2.98

3.29

1.604

1.643

1.627

1.675

http://www.geminterest.com 

Dravite

1.604

1.675

0.016

0.032

2.9

3.29

1.604

1.643

1.627

1.675

Joel Arem, Color Encyclopedia of Gemstones, 1987 

Dravite

1.604

1.675

0.016

0.032

2.9

3.29

1.604

1.643

1.627

1.675

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

Dravite

1.604

1.675

0.016

0.032

3.1

3.9

 

 

 

 

Gemology Tools Professional 2010

Dravite

1.612

1.661

0.019

0.03

3

3.2

 

 

 

 

Gemmo.eu 2013

Elbaite

1.603

1.655

0.013

0.024

2.84

3.1

 

 

 

 

http://www.gemmology.be 

Elbaite

1.603

1.655

0.013

0.024

2.84

3.2

1.603

1.634

1.619

1.655

http://www.geminterest.com 

Elbaite

1.603

1.655

0.013

0.024

2.84

3.1

1.603

1.634

1.619

1.655

Joel Arem, Color Encyclopedia of Gemstones, 1987 

Elbaite

1.603

1.655

0.013

0.025

2.84

3.17

1.603

1.634

1.619

1.655

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

Elbaite

1.603

1.655

0.013

0.024

3

3.26

 

 

 

 

Gemology Tools Professional 2010

Elbaite

1.615