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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

Corundum - Sapphire

1.758

1.766

0.008

0.008

3.99

4.01

yellow, colourless, blue

Kimmirut, Baffin Island, Canada

 

 

 

 

 

 

very weak orange

moderate orange

Gems & Gemology 2004 winter p344

Corundum - Sapphire

1.758

1.767

0.009

0.009

 

 

pale to dark pink

Kootchinskoye deposit, Ural Mts, Russia

<1ct

 

 

 

 

 

 

 

Gems & Gemology 1994 winter p243-252

Corundum - Sapphire

1.758

1.767

0.007

0.007

3.91

4.35

bluish grey

Santa Terezinha de Goias, Brazil

only for cabochon, translucent

1.758

1.760

1.765

1.767

 

 

 

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1986 Jg 35, Nr 1/2,p15-19

Corundum - Sapphire

1.758

1.77

0.008

0.01

3.98

4.02

Blue, grey, bicolored pink and blue, violetish blue, purplish pink, colourless

Sutara, Jewish Autonomous Oblast' Russia

 

1.767

1.770

1.758

1.762

 

inert, purplish pink stones: inert to weak red

inert,  purplish pink stones:moderate to strong red

Gems & Gemology 2016 Fall, p 252-264

Corundum - Sapphire

1.759

1.768

0.008

0.008

4

4.03

purplish pink

Batakundi, Pakistan

 

1.759

1.760

1.767

1.768

 

very weak red

moderate to strong red

Gems & Gemology 2004 winter p343

Corundum - Sapphire

1.759

1.77

0.009

0.009

3.99

4.01

very dark inky blue, yellow

Kaduna Province, Nigeria

 

1.768

1.770

1.759

1.761

 

 

 

The Journal of Gemmology 1987 Vol 20, N°7/8 p427-442

Corundum - Sapphire

1.759

1.77

0.008

0.008

3.97

3.99

pink to light red, reddish violet

Nepal

 

1.759

1.762

1.767

1.770

 

intens reddish-orange

stronger than UVS:intens reddish-orange

The Australian Gemmologist 1982 may, p225-229

Corundum - Sapphire

1.759

1.77

0.011

0.011

3.09

3.09

greenish brown

Sri Lanka

 

 

 

 

 

absorption lines in blue and violet

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1998 Sep, p169

Corundum - Sapphire

1.759

1.771

0.008

0.009

3.98

4.04

pink, purplish pink, light to dark blue

Quy Chau - Quy Hop, Nghe An,  Vietnam

 

1.767

1.771

1.759

1.762

 

blue: light blue, orange

blue: light blue, orange

Gems & Gemology 2012 Fall 2012, p165

Corundum - Sapphire

1.759

1.769

0.008

0.009

 

 

medium to medium dark blue to slightly violetish blue

Madagascar

 

1.759

1.760

1.768

1.769

Fe lines

inert to weak challky greenish blue

inert

Gems & Gemology 1995 Summer, p132-133

Corundum - Sapphire

1.76

1.768

0.008

0.008

4

4

blue

Elahera, Sri Lanka

 

 

 

 

 

450nm, 460nm

light blue

 

Gems & Gemology 1986 Summer, p87

Corundum - Sapphire

1.76

1.768

0.008

0.008

4.01

4.01

yellow

Elahera, Sri Lanka

 

 

 

 

 

694, 692nm

apricot orange

apricot reddish

Gems & Gemology 1986 Summer, p87

Corundum - Sapphire

1.76

1.768

0.008

0.008

4

4

padparadscha

Elahera, Sri Lanka

 

 

 

 

 

694 and 692nm

strong apricot

 

Gems & Gemology 1986 Summer, p87

Corundum - Sapphire

1.76

1.77

0.008

0.009

3.94

4.01

red to pink, purplish pink, often with visible violetish blue color banding

Ganesh HimalNepal

 

1.760

1.762

1.769

1.770

468 line, 475 line, 476 line, 525-585 band, 659 line, 668 line, 692 line, 694 line

red: faint to moderate red; violet : inert

red : moderate to very strong red; violet : inert

Gems & Gemology 1997 spring p24-41

Corundum - Sapphire

1.76

1.769

0.008

0.008

3.98

4

orange pink, purplish pink, blue

Ilakaka, Madagascar

 

 

 

 

 

pink : Cr ; blue : 450 band

very weak orange ; blue : inert to chalky yellowish green

moderate to strong orange; blue : inert to very weak red

Gems & Gemology 1999 summer p149

Corundum - Sapphire

1.76

1.772

0.008

0.01

4

4.02

blue to violetish blue to purple, colour change (violet in daylight-purple in incandescent light)

Indaia, Minas Gerais, Brazil

geology: Precambrian complexes of metamorphic besement rocks

1.760

1.762

1.768

1.772

faint band at 450nm

inert

moderate to strong bright red

Gems & Gemology 1994 spring, p24-32

Corundum - Sapphire

1.76

1.771

0.008

0.008

3.99

4.02

 

Indaia, Minas Gerais, Brazil

 

1.760

1.763

1.768

1.771

band 500-600nm (Fe²+/Ti4+) and  450nm (Fe³+)

inert

inert, sometimes reddish

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1994 Dez, p111-116

Corundum - Sapphire

1.76

1.77

0.008

0.008

3.98

4

blue, pink, colourless, pale green, yellow, orange, pale brown, brownish red, violet

Madagascar

up to 15ct

1.760

1.762

1.768

1.770

 

 

 

The Journal of Gemmology 2001 Vol27, N°7,p385-394

Corundum - Sapphire

1.76

1.77

0.008

0.009

3.94

4.09

pink and blue

Muling, Heilongjiang, China

 

1.760

1.762

1.768

1.770

 

 

 

Gems & Gemology 2011 Summer, p136

Corundum - Sapphire

1.76

1.772

0.008

0.01

3.96

4

 

Nigeria

 

1.760

1.764

1.770

1.772

 

 

 

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1986 Jg 35, Nr 1/2,p15-19

Corundum - Sapphire

1.76

1.773

0.008

0.008

3.98

4.03

blue, blue-violet, greenish blue, greenish-yellow, yellow

Nosy-Bé, Madagascar

Basalt

1.768

1.773

1.760

1.765

 

inert

inert

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2004 Dec, p143-158

Corundum - Sapphire

1.76

1.769

0.009

0.009

3.98

3.98

colourless

Sri Lanka

1.4ct

 

 

 

 

 

 

pinkish-orange

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1999 Jul p106

Corundum - Sapphire

1.76

1.77

0.008

0.008

4

4

blue

Thammannawa, Kataragama area, Sri Lanka

 

1.768

1.770

1.760

1.762

line at 450nm

inert

weak red

Gems & Gemology 2012 Summer, p98-107

Corundum - Sapphire

1.76

1.769

0.008

0.009

4

4

purplish pink to orangy pink, brownish pinkish purple, bicolored reddish purple and reddish
orange

Tamil Nadu, India

0.36-1.70ct

 

 

 

 

weak absorption band at 460 nm, a 475/480 nm doublet, and a band at 670 nm

inert to weak red

weak to moderate red

Gems & Gemology 2005 fall, p268-269

Corundum - Sapphire

1.76

1.769

0.008

0.009

4.02

4.05

bicoloured: pink and blue

Tunduru, Tanzania

0.64 and 1.97 ct

1.760

1.760

1.768

1.769

Cr

inert

moderate-to-strong orange

Gems & Gemology 1999 Winter, p215

Corundum - Sapphire

1.76

1.768

0.008

0.008

3.99

3.99

purplish pink

Palmer Canyon, Laramie Mts, Wyoming

1.15 ct

 

 

 

 

chromium lines and a 470 nm doublet

very weak red

moderate orangy red

Gems & Gemology 2001 Winter, p337

Corundum - Sapphire

1.76

1.769

0.008

0.009

4

4

purplish pink to orangy pink

Tamil Nadu, Inia

 

 

 

 

 

weak absorption band at 460 nm, a 475/480 nm doublet, and a band at 670 nm

inert to weak red

weak to moderate red

Gems & Gemology 2005 Fall, p268

Corundum - Sapphire

1.76

1.772

0.008

0.008

3.96

4.01

greenish to violetish blue

Bawmar Mine, Mogok, Myanmar

0.20 to 1.63ct

1.760

1.764

1.768

1.772

 

inert

inert

Gems & Gemology 2013 Winter, p223-232

Corundum - Sapphire

1.760

1.770

0.01

0.01

3.95

4.05

bronze metallic sheen (body colour : blue, green or yellow)

eastern Kenya

Gold Sheen sapphire, 105 stones from 1 to 30ct, sheen effect originates from reflection of light from exsolved hematite-ilmenite

 

 

 

 

absorption at 450nm

inert

inert

The Journal of Gemmology 2015 Vol 38, No 8, p678-691

Corundum - Sapphire

1.76

1.77

0.01

0.01

4

4.02

green

 

0.89ct to 5.90ct, lead glass filled;Growth tubes, ‘fingerprints’, lamellar twinning, orange and blue flash effects along filled fissures, green colour concentrations in filled fissures and cavities, flattened gas bubbles trapped in the  glass filler

 

 

 

 

 

Inert

Inert to weak orange

The Journal of Gemmology 2015 Vol 34, No.5, p420-427

Corundum - Sapphire

1.76

 

 

 

3.87

3.87

light pink

 

2.77ct, semi-transparent cabochon,  Filled with Bismuth-Based Glass

 

 

 

 

 

weak red

medium red

Gems & Gemology 2017 Spring, p94

Corundum - Sapphire

1.761

1.773

0.008

0.008

3.99

4.02

Homogeneous colouration is rare. More common is distinct colour zoning with blue-violet, greenish blue to greenish yellow and yellow domains; star sapphires: grey to blue

Ambondromifehy, Antsiranana Province, Madagascar

geology: magmatic (alkali basalts)

1.761

1.765

1.769

1.773

 

inert

inert

Gems & Gemology 2000 Fall p 216-233

Corundum - Sapphire

1.761

1.771

0.008

0.008

3.91

3.98

blue

Andranondambo, Madagascar

 

1.761

1.763

1.769

1.771

450nm band

inert to weak greenish blue

inert

The Journal of Gemmology 1996 Vol 25, N°3, p177-184

Corundum - Sapphire

1.761

1.771

0.008

0.008

3.91

3.98

blue

Andranondambo, Madagascar

 

1.761

1.763

1.769

1.771

bands at 570nm and 450nm

inert, rarely weak greenish-blue or weak orange

inert

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1996 Mar, p13-22

Corundum - Sapphire

1.761

1.774

0.008

0.009

3.97

4.02

light blue, dark blue, green, yellow, gold

Australia

 

1.761

1.765

1.769

1.774

Fe lines

inert

inert

Gems & Gemology 1985 fall p130-146

Corundum - Sapphire

1.761

1.771

0.008

0.008

3.91

3.98

pale to dark blue

Bekily, Toliara Province, Madagascar

0.49 - 1.32 ct

1.761

1.763

1.769

1.771

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1995 Mar, p3

Corundum - Sapphire

1.761

1.769

0.008

0.008

4

4

blue

Bo Ploi, Kanschanaburi, Thailand

 

 

 

 

 

absorption lines around 450-460nm

inert

inert

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1991 Dez, p165-180

Corundum - Sapphire

1.761

1.771

0.009

0.009

3.998

4.005

dark blue

Cyangugu district, Rwanda

basaltic type

1.761

1.762

1.770

1.771

375, 390, 450nm

inert

inert

The Journal of Gemmology 1996 Vol 25, N°2, p90-106

Corundum - Sapphire

1.761

1.769

0.008

0.008

4

4

blue

Kanchanaburi, Thailand

 

 

 

 

 

450nm, 460nm

inert

inert

The Journal of Gemmology 1984 Vol 19, N°3, p228-239

Corundum - Sapphire

1.761

1.77

0.009

0.009

4.03

4.03

blue

Maydan Shahr, Afghanistan

 

 

 

 

 

450, 460, 470

inert

inert

Gems & Gemology 2004 winter p343

Corundum

1.761

1.77

0.008

0.008

3.98

3.99

 

Mong Hsu, Myanmar

trapiche ruby and sapphire

1.761

1.762

 

 

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1996 Mar, p23-24

Corundum - Sapphire

1.761

1.77

0.008

0.008

3.99

4

pink, pink+blue

Neelum Valley

 

1.761

1.762

1.769

1.770

Cr + Fe

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2005 Sep, p111-114

Corundum - Sapphire

1.761

1.77

0.008

0.009

3.99

4.02

purplish pink to purplish red

Pamir Mts, Tajikistan

0.3 to 1.48ct, transparent

1.761

1.762

1.770

1.770

cut-off 450, lines : 468, 475, 476, broad band 530-580, lines 659, 692, 694

very weak to medium : red

strong to very strong : slightly orangy-red to red

The Journal of Gemmology 1998 Vol26, N°2, p103-109

Corundum - Sapphire

1.761

1.771

0.009

0.009

3.99

4.02

purplish blue to blue-grey

Penglai mine, Hainan Island, China

 

 

 

 

 

bands at 450 , 460nm and 470nm

inert

inert

Gems & Gemology 1988 Fall p155-160

Corundum - Sapphire

1.761

1.769

0.008

0.008

3.98

4.02

padparadschah, pinkish-orange to pinkish-yellow

Sri Lanka

 

 

 

 

 

 

weak yellowish pink

strong pinkish orange

The Journal of Gemmology 1985 Vol 19, No 5 p389-403

Corundum - Sapphire

1.761

1.77

0.008

0.009

3.95

3.97

light blue

Wellawaya, Sri Lanka

 

1.761

1.762

1.769

1.770

 

inert

inert

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2008 57/1-2, p28-29

Corundum - Sapphire

1.761

1.772

0.008

0.009

3.91

4.02

colourless, orange, grey, pink, light to dark blue

Tan Huong-Truc Lau, Yen Bai, Vietnam

 

1.769

1.772

1.761

1.763

 

grey/colourl: orange; blue: light blue/orange; orange: orange-red

grey/colourl: orange; blue: light blue/orange; orange: strong orange-red

Gems & Gemology 2012 Fall 2012, p162

Corundum - Sapphire

1.761

1.771

0.008

0.009

4

4.03

pink-brown through brownish pink and purple (incandescent light), yellowish
brown, greyish violet, and greyish greenish blue (fluorescent light)

Tanzania

1.06-2.16 ct

1.761

1.762

1.770

1.771

absorption features typical of ruby and lines at about 450, 460, and 470 nm.

inert

inert

Gems & Gemology 1995 Spring, p64-65

Corundum - Sapphire

1.762

1.771

0.008

0.008

3.97

4

blue, yellow, bicoloured blue and yellow

Ambondromifehy, Antsiranana Province, Madagascar

 

1.762

1.763

1.770

1.771

blue : bands 450, 387, 377nm

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1997 Sep, p123-124

Corundum - Sapphire

1.762

1.775

0.008

0.01

3.95

4.05

blue

Loch Roag, Isle of Lewis, Scotland

 

1.762

1.767

1.772

1.775

diffuse braod band at 450nm

inert

inert

The Journal of Gemmology 1984 Vol XIX, N°4, p336-342

Corundum - Sapphire

1.762

1.77

0.008

0.008

3.97

3.99

blue

Malawi

 

 

 

 

 

 

 

 

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1990 Apr, p89-92

Corundum - Sapphire

1.762

1.77

0.008

0.008

3.99

4.02

blue, green are most common, yellow, pink, red  in lesser quantities

Mercaderes-io mayo area, Cauca, Colombia

 

 

 

 

 

 

inert

inert and weak to moderate orange to red

Gems & Gemology 1985 spring p20-25

Corundum - Sapphire

1.762

1.77

0.008

0.008

3.98

3.99

pink, violet-red, violet, lilac, blue-lilac, bicoloured yellow/blue and yellow/violet

Municipio de Mahuacu, Sacramento, Minas Gerais, Brazil

 

 

 

 

 

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 2000 Sep, p173-174

Corundum - Sapphire

1.762

1.774

0.008

0.009

3.93

3.99

pink, brownish-red, red

Ngoronghoro, Morogoro Region,Tanzania

 

1.762

1.765

1.770

1.774

 

 

 

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1989 Apr, p44-46

Corundum - Sapphire

1.762

1.771

0.009

0.009

 

 

dark blue, nearly opaque in overhead light, translucent and transparent in transmitted light; areas of blue and bluish green

Penglai, Hainan Island, China

 

 

 

 

 

very straong bands at 450 and 460 that nearly merge, and narrower band at 470nm

inert

inert

Gems & Gemology 1988 Fall, p155-160

Corundum - Sapphire

1.762

1.77

0.008

0.008

3.92

4.17

blue

 

cobalt-doped glass-filled; Strong red to orange-red with chelsea filter, red colour concentrated in the fissures

 

 

 

 

lines at 450, 460, 471 nm; Co-glass spectrum from the glass

inert to weak red

inert to weak red

http://www.ruby-sapphire.com/glass-filled-sapphire.htm 2013

Corundum - Sapphire

1.762

1.77

0.008

0.008

40

4.01

dark blue

 

star sapphire, semi-transparent to semi-translucent

 

 

 

 

bands at 450, 460, and 470 nm

inert

inert

Gems & Gemology 1998 Summer, p140-141

Corundum - Sapphire

1.762

1.77

 

 

 

 

blue

Kashmir, India

6.70 ct

 

 

 

 

line at 450 nm (Fe) and in the red (Cr

inert

inert

Gems & Gemology 1983 Summer, p74

Corundum - Sapphire

1.762

1.77

0.008

0.008

4.03

4.03

orangy yellow

 

filled with lead glass, 4.27 ct

 

 

 

 

absorption band at around 450nm

reddish orange

reddish orange

Gems & Gemology 2014 Spring, p92-93

Corundum - Sapphire

1.762

1.772

0.008

0.009

3.98

4.01

yellow+blue+green+brown, "gold sheen"

 

gold sheen sapphire, 14 sapphires up to 97.69ct

 

 

 

 

 

inert

inert

Gems & Gemology 2016 Winter, p413-414

Corundum - Sapphire

1.763

1.775

0.008

0.008

3.99

4.03

 

Madagascar

 

1.763

1.767

1.771

1.775

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1996 Dec, p155

Corundum - Sapphire

1.763

1.773

0.008

0.008

3.97

3.98

orange (padparadscha)

Malawi

 

1.763

1.765

1.771

1.773

 

 

 

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1989 Dec, p164-165

Corundum - Sapphire

1.763

1.773

0.008

0.008

3.99

4.06

reddish brown

Umba Valley, Tanzania

0.88 to 7.8 ct

1.763

1.765

1.771

1.773

450nm line, 693nm doublet

 

 

The Journal of Gemmology 1984 Vol 19, N°2, p139-144

Corundum - Sapphire

1.763

1.774

0.008

0.01

 

 

 greenish yellow

Ploi Waen area of Chanthaburi, Thailand

 

1.763

1.765

1.772

1.774

 

 

 

Gems & Gemology 2016 Fall, p 325-326

Corundum - Sapphire

1.764

1.772

0.008

0.008

3.98

3.98

blue

China

 

 

 

 

 

 

 

 

Gemmologie, Zeitschrift der Deutschen Gemmologischen Gesellschaft 1997 Jun, p64

Corundum - Sapphire

1.764

1.773

0.009

0.009

3.97

3.97

 

Lodwar, Lake Turkana, Kenya

 

 

 

 

 

 

 

 

Zeitschrift der Deutschen Gemmologischen Gesellschaft 1989 Aug, p89-94

Corundum - Sapphire

1.764

1.772

0.008

0.008

3.98

4.03

dark blue to very dark blue

Maydan Sahr, Afghanistan

0.40 and 0.72 ct

 

 

 

 

450, 460, and 470 nm bands

inert

inert

Gems & Gemology 2002 Summer, p181

Corundum - Sapphire

1.764

1.775

0.008

0.01

 

 

yellow

Anakie area in Queensland, Australia

 

1.764

1.766

1.773

1.775

 

 

 

Gems & Gemology 2016 Fall, p 325-326

Corundum - Sapphire

1.765

1.773

0.008

0.008

3.98

4.06

brownish-orange

Tanzania

 

 

 

 

 

 

inert

inert

The Journal of Gemmology 1985 Vol 19, No 5 p389-403

Corundum - Sapphire

1.765

1.775

0.01

0.01

3.95

4.03

yellow to brownish green to blue

Yabelo, Ethiopia

 

 

 

 

 

bands at 450, 460, 470nm

inert

inert

Gems & Gemology 2011 Fall, p247

Corundum - Sapphire

1.768

1.777

0.009

0.009

3.98

4.05

yellow-brown, reddish orange

Kalalani, Tanzania

 

 

 

 

 

450nm

none

none

Gems & Gemology 1999 summer p116

Corundum - Sapphire

1.78

1.788

0.008

0.008

 

 

pink

 

0.95ct, Cr-diffused

 

 

 

 

Cr

weak red  with chalky blue-white patches

strong red

The Journal of Gemmology 2015 Vol 34, No.6, p486-488

 

TABLES

Stone

RI min

RI max

Biref min

Biref max

Dens min

Dens max

ne min

ne max

no min

no max

Reference

Corundum

1.757

1.779

0.008

0.009

3.99

4.1

 

 

 

 

http://www.gemmology.be 

corundum

1.757

1.779

0.007

0.009

3.8

4.06

1.757

1.770

1.765

1.779

http://www.geminterest.com 

Corundum - Sapphire

1.757

1.774

0.008

0.009

3.99

4.01

1.757

1.765

1.766

1.774

http://www.geminterest.com 

Corundum

1.757

1.779

0.08

0.009

3.97

4.1

1.757

1.770

1.765

1.779

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

Corundum - Sapphire

1.757

1.779

0.008

0.01

3.95

4.1

 

 

 

 

Gemology Tools Professional 2010

corundum

1.758

1.78

0.007

0.01

3.9

4.05

1.758

1.770

1.766

1.780

Gemmological Tables, Ulrich Henn, 2004 

corundum

1.759

1.778

0.008

0.008

3.97

4.03

1.759

1.769

1.767

1.778

Tabellen zur Edelstein-Bestimmung, Pschichholz FGA, 1975 

Corundum - Sapphire

1.76

1.775

0.008

0.009

3.9

4.05

 

 

 

 

Gemmo.eu 

Corundum - Sapphire

1.762

1.78

0.008

0.008

3.95

4.03

 

 

 

 

Bestimmungstabellen für Edelsteine, Birgit Günther, 1981 

Corundum - Sapphire

 

 

 

 

3.96

4.05

 

 

 

 

John Sinkakas, Gemstone and mineral data book,1972 

 

CAUSE OF COLOUR

Stone

Colour

Cause of colour

Reference

Corundum - Sapphire

blue

Fe²+-O-Ti4+ charge transfer with influence of Fe²+->Fe³+ charge transfer

Gems & Gemology Summer 1988

Corundum - Sapphire

colour-change

Cr³+and/or V³+in octahedral coordination in a particular range of concentration

Gems & Gemology Summer 1988

Corundum - Sapphire

dark brown

Mechanical colour due to dark brown colour of exsolved hematite plates (mainly black star sapphire)

Weibel&essicken (1981)(Ruby & Sapphire, Hughes 1997)

Corundum - Sapphire

green

Ion pair transitions on individual ions of pair Fe³+ - Fe³+, plus Fe2+->Ti4+ charge transfer

Emmett&Douthit (1993) (Ruby & Sapphire, Hughes 1997)

Corundum - Sapphire

green

Combination of one of the yellow causes with blue cause

Nassau (1994) (Ruby & Sapphire, Hughes 1997)

Corundum - Sapphire

greyish blue

Fe²+ -> Fe³+ intervalence charge transfer (without Fe³+-O-Ti4+ charge transfer)

Gems & Gemology 1993 Fall p151

Corundum - Sapphire

orange pink (padparadscha)

Cr4+ in octahedral coordination due to Cr4+ and Mg²+ substituting for two Al³+ in the crystal structure

Gems & Gemology Summer 1988

Corundum - Sapphire

orange to orange-brown

Cr³+ in octahedral coordination and one or more of the yellow causes

Emmett&Douthit (1993) (Ruby & Sapphire, Hughes 1997)

Corundum - Sapphire

orange-brown heated

orange colour centers, Mg +Cr +Fe

The Journal of Gemmology, 2004,29,3,149-182

Corundum - Sapphire

orangey-yellow diffusion treated

Be + (Cr,Fe,Mg) dopant (causing colour center)

The Journal of Gemmology, 2004,29,3,149-182

Corundum - Sapphire

pale brown diffusion treated

Be dopant (causing colour center)

The Journal of Gemmology, 2004,29,3,149-182

Corundum - Sapphire

pink

Cr³+ in octahedral coordination

Gems & Gemology Summer 1988

Corundum - Sapphire

pink orange, orange-red, diffusion treated

Be + (Cr,Fe) dopant (causing colour center)

The Journal of Gemmology, 2004,29,3,149-182

Corundum - Sapphire

purple

Fe²+-O-Ti4+ charge transfer coexisting with Cr³+ in octahedral coordination

Gems & Gemology Summer 1988

Corundum - Ruby

red

Cr³+ in octahedral coordination which have replaced Al³+

Fritsch&Rossman (1987) (Ruby & Sapphire, Hughes 1997)

Corundum - Sapphire

reddish-orange

Mn³+

The Journal of Gemmology, 2000, Vol27, N°1, p2

Corundum - Sapphire

yellow

O²- ->Fe³+ charge transfer

Schmetzer 1982, Nassau 1987, Gems & Gemology Summer 1988

Corundum - Sapphire

yellow

Ion pair transitions on individual ions of pair Fe³+ - Fe³+

Fergusson and Fielding 1971, Gems & Gemology Summer 1988

Corundum - Sapphire

yellow

Colour center hole pair resulting from insufficient charge when any divalent impurity (such as Mg²+) replaces Al³+

Emmett&Douthit (1993) (Ruby & Sapphire, Hughes 1997)

Corundum - Sapphire

yellow

A variety of colour centers

Nassau&Valente (1987) (Ruby & Sapphire, Hughes 1997)

Corundum - Sapphire

yellow diffusion treated

Be + Fe dopant (causing colour center)

The Journal of Gemmology, 2004,29,3,149-182

Corundum - Sapphire

yellow diffusion treated

Be + (Fe,Mg) dopant (causing colour center)

The Journal of Gemmology, 2004,29,3,149-182

 

MINERAL INCLUSIONS

Inclusion

Stone

Reference

albite

Corundum - Sapphire

E.J. Gübelin and J.I. Koivula, Photoatlas of inclusions in Gemstones, volume 2 (2005)

allanite

Corundum - Sapphire

Delaunay A. Univ. de Nantes, étude (2003-2004) http://aurelien.delaunay.free.fr

almandine

Corundum - Sapphire

Joel Arem, Color Encyclopedia of Gemstones, 1987

analcime

Corundum - Sapphire

Gübelin & Koivula 1986

andesine

Corundum - Sapphire

Gems & Gemology Winter 2015 p 379

anorthite

Corundum - Sapphire

Internal World of Gemstones, Gübelin, 1983

apatite

Corundum - Sapphire

Gemmological Tables, Ulrich Henn , GGA, 2004

baddeleyite

Corundum - Sapphire

Journal of Gemmology 1997, 25, 7, p453-516

barite

Corundum - Sapphire

Gems & Gemology Winter 2015 p 379

biotite

Corundum - Sapphire

Joel Arem, Color Encyclopedia of Gemstones, 1987

boehmite

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

brookite

Corundum - Sapphire

Gübelin & Koivula 1986

bytownite

Corundum - Sapphire

Gems & Gemology Winter 2015 p 379

calcite

Corundum - Sapphire

Gemmological Tables, Ulrich Henn , GGA, 2004

chalcopyrite

Corundum - Sapphire

Internal World of Gemstones, Gübelin, 1983

chlorite

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

chondrodite

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

clinozoisite

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

columbite

Corundum - Sapphire

Internal World of Gemstones, Gübelin, 1983

corundum

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

cristobalite

Corundum - Sapphire

Gems & Gemology Winter 2015 p 379

diamond

Corundum - Sapphire

Gems & Gemology 1997 winter p299

diaspore

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

diopside

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

dolomite

Corundum - Sapphire

Ruby & Sapphire, R. Hughes, 1997

dravite

Corundum - Sapphire

Delaunay A. Univ. de Nantes, étude (2003-2004) http://aurelien.delaunay.free.fr

epidote

Corundum - Sapphire

E.J. Gübelin and J.I. Koivula, Photoatlas of inclusions in Gemstones, volume 2 (2005)

fassaite

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

felspar

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

fergusonite

Corundum - Sapphire

Joel Arem, Color Encyclopedia of Gemstones, 1987

fluorite

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

gahnospinel

Corundum - Sapphire

Ruby & Sapphire, R. Hughes, 1997

gibbsite

Corundum - Sapphire

Gems & Gemology Winter 2015 p 379

glass

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

goethite

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

graphite

Corundum - Sapphire

Joel Arem, Color Encyclopedia of Gemstones, 1987

hedenbergite

Corundum - Sapphire

Gems&Gemology summer 1996

hematite

Corundum - Sapphire

Delaunay A. Univ. de Nantes, étude (2003-2004) http://aurelien.delaunay.free.fr

hercynite

Corundum - Sapphire

Ruby & Sapphire, R. Hughes, 1997

hornblende

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

humite

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

ilmenite

Corundum - Sapphire

Joel Arem, Color Encyclopedia of Gemstones, 1987

kaolinite

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

kyanite

Corundum - Sapphire

E.J. Gübelin and J.I. Koivula, Photoatlas of inclusions in Gemstones, volume 2 (2005)

labradorite

Corundum - Sapphire

Gems & Gemology Winter 2015 p 379

magnetite

Corundum - Sapphire

Gems & Gemology Winter 2015 p 379

margarite

Corundum - Sapphire

Joel Arem, Color Encyclopedia of Gemstones, 1987

mica

Corundum - Sapphire

http://www.gemresearch.ch

monazite

Corundum - Sapphire

Internal World of Gemstones, Gübelin, 1983

muscovite

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

nahcolite

Corundum - Sapphire

Gems & Gemology Winter 2015 p 379

nordstrandite

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

olivine

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

orthoclase

Corundum - Sapphire

Gems & Gemology Winter 2015 p 379

pargasite

Corundum - Sapphire

Joel Arem, Color Encyclopedia of Gemstones, 1987

pentlandite

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

phlogopite

Corundum - Sapphire

http://www.gemresearch.ch

plagioclase

Corundum - Sapphire

Internal World of Gemstones, Gübelin, 1983

pyrite

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

pyrochlore

Corundum - Sapphire

Gems & Gemology Winter 2015 p 379

pyrope

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

pyrrhotite

Corundum - Sapphire

http://www.gemresearch.ch

quartz

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

rutile

Corundum - Sapphire

Gemmological Tables, Ulrich Henn , GGA, 2004

sapphirine

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

scapolite

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

spessartine

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

sphalerite

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

spinel

Corundum - Sapphire

http://www.gemresearch.ch

sulphur

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

thorianite

Corundum - Sapphire

Journal of Gemmology 1997, 25, 7, p453-516

thorite

Corundum - Sapphire

Joel Arem, Color Encyclopedia of Gemstones, 1987

titanite

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

topaz

Corundum - Sapphire

Gems & Gemology Winter 2015 p 379

tourmaline

Corundum - Sapphire

Gems & Gemology 1990 winter

uraninite

Corundum - Sapphire

http://www.gemresearch.ch

uranpyrochlore

Corundum - Sapphire

Internal World of Gemstones, Gübelin, 1983

uvite

Corundum - Sapphire

Gems & Gemology Spring 1997

vermicullite

Corundum - Sapphire

Ruby & Sapphire, Hughes 1997

zirconolite

Corundum - Sapphire

Journal of Gemmology 1997, 25, 7, p453-516

zirconolite

Corundum - Sapphire

Gemmological Tables, Ulrich Henn , GGA, 2004

zoisite

Corundum - Sapphire

Joel Arem, Color Encyclopedia of Gemstones, 1987

 

LOCALITIES

STONE

LOCALITIES

REFERENCE

Corundum-Sapphire

 

Maydan Shahr

 

Afghanistan

Gems & Gemology 2004 Winter p343

Corundum-Sapphire

 

Inverell

New South Wales

Australia

Carroll, J. (2002)

Corundum-Sapphire

VulcanState forest

Oberon

New south Wales

Australia

Gems & Gemology 2000 winter p316

Corundum-Sapphire

 

Anakie

Queensland

Australia

Geïllustreerde Mineralen Encyclopedie, Petr Korbel & Milan Novak, 2001

Corundum-Sapphire

 

Jauru

Matto Grosso

Brazil

Joel Arem, Color Encyclopedia of Gemstones, 1987

Corundum-Sapphire

 

Indala

Minas Gerais

Brazil

Gems & Gemology 2000 winter p316

Corundum-Sapphire

 

Chamnop

Cardamom

Cambodja

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Pailin District

Krong Pailin (Pailin) Municipality

Cambodja

Joel Arem, Color Encyclopedia of Gemstones, 1987

Corundum-Sapphire

Phnum Ko Ngoap

Pailin District

Krong Pailin (Pailin) Municipality

Cambodja

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Phnum O Tang

Pailin District

Krong Pailin (Pailin) Municipality

Cambodja

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Phnum Yat

Pailin District

Krong Pailin (Pailin) Municipality

Cambodja

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Bo Kham

Virochey

Rattanakiri (Rotanokiri) Province

Cambodja

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Bokeo

Virochey

Rattanakiri (Rotanokiri) Province

Cambodja

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Voeune Sai

Virochey

Rattanakiri (Rotanokiri) Province

Cambodja

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Chamnom

Rovieng

Cambodja

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Passmore (Blu Moon, Blu starr, Sapphire Hill)

Slocan Valley

British Columbia

Canada

Gems & Gemology 2000 winter p316

Corundum-Sapphire

Beluga

Baffin Island

Nunavut Territory

Canada

InColor Fall-Winter 2007-2008, p17

Corundum-Sapphire

Kimmirut

Baffin Island

Nunavut Territory

Canada

InColor Fall-Winter 2007-2008, p17

Corundum-Sapphire

Penglai Gem deposit, Penglai

Ding'an

Hainan Province (Hainan Island)

China

Qiu Zhili et al (2005): Chinese Science Bulletin 50(22), 2602-2611.

Corundum-Sapphire

 

Mulan

Heilongjiang Province (Manchuria; Dongbei Region)

China

Gems & Gemology 2000 winter p314

Corundum-Sapphire

Liuhe

Fujian

Jiangsu

China

Gems & Gemology 2000 winter p314

Corundum-Sapphire

Mingxi

Fujian

Jiangsu

China

Gems & Gemology 2000 winter p314

Corundum-Sapphire

 

 

Qinghai (Chinghai) Province

China

Gems & Gemology 2000 winter p314

Corundum-Sapphire

Sapphire deposit, Wutu, Changle

Weifang Prefecture

Shandong Province

China

Qiu Zhili, et al(2005): Chinese Science Bulletin 50(22), 2602-2611.

Corundum-Sapphire

 

Taxkorgan

Xinjiang (Xinjiang-Uygur) Autonomous Region

China

Gems & Gemology 2000 winter p314

Corundum-Sapphire

 

Mercaderes

Cauca Department

Colombia

Gems & Gemology 2003 winter p330

Corundum-Sapphire

 

Mercaderes

Cauca Department

Colombia

Gems & Gemology 2000 fall p268

Corundum-Sapphire

 

southwest coast

 

Greenland

Gems & Gemology 2009 Winter p249

Corundum-Sapphire

 

Anatapur

Andhra Pradesh

India

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Kakinada

Andhra Pradesh

India

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Khaman

Andhra Pradesh

India

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Nellore

Andhra Pradesh

India

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Soomjam

Kargil

Jammu and Kashmir

India

Gems & Gemology 2000 winter p314

Corundum-Sapphire

 

Hassan

Karanataka

India

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Kolar

Karanataka

India

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Tumkur

Karanataka

India

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Travancore

Kerala

India

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Trivandrum

Kerala (Travancore)

India

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Banjipadar

Kalahandi

Orissa

India

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Sargiguda

Kalahandi

Orissa

India

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Amera

Nawapada

Orissa

India

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Katamal

Nawapada

Orissa

India

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Chinnadharapuram

Kangayam

Tamil Nadu

India

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Malaipatti

Kangayam

Tamil Nadu

India

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Semizbugy

Qaraghandy Oblysy (Karaganda Oblast')

Kazakhstan

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Chania River

Thika

Central Province

Kenya

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Kubi Kan

Chandler's Falls

Eastern Province

Kenya

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Garba Tula

Eastern Province

Kenya

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Kinyiki Hill

Mtitio Andei

Eastern Province

Kenya

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Lodwar

Kenya Rift Valley

Kenya

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Don Dol

Loldaika Hills

Kenya Rift Valley

Kenya

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Samburu

Mararal

Kenya Rift Valley

Kenya

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Murua Rith Hills

Kenya Rift Valley

Kenya

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Pelekech Mountains

Kenya Rift Valley

Kenya

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

West Pokot

Kenya Rift Valley

Kenya

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Ban Huai Sai (Ban Houay Xai)

Annam Highlands

 

Laos

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Antanifotsy pegmatite, Faratsiho Department

Vakinankaratra Region (Betafo - Antsirabé region)

Antananarivo Province

Madagascar

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Ambilobe

Antsiranana Province

Madagascar

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Amboudrohefeha

Ambondromifehy

Antsiranana Province

Madagascar

Gems & Gemology 2000 Winter p315

Corundum-Sapphire

 

Milanoa

Antsiranana Province

Madagascar

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Andranolava

Fianarantsoa Province

Madagascar

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Marosely sapphire deposit, Ranotsara North Commune, Iakora District

Horombe Region

Fianarantsoa Province

Madagascar

The Journal of Gemmology 2009, Vol 31/N°5-8, p171-179

Corundum-Sapphire

Sahambano, Ihosy, Ihosy Department

Horombe Region

Fianarantsoa Province

Madagascar

Giuliani, G., Fallick, A.,et al (2007): Mineralium Deposita 42, 251-270.

Corundum-Sapphire

Zazafotsy Quarry, Ambahatraso, Amboarohy, Ihosy, Ihosy Department

Horombe region

Fianarantsoa Province

Madagascar

Giuliani, G., et al (2007): Mineralium Deposita 42, 251-270.

Corundum-Sapphire

Bekily

Amboasary

Tuléar (Toliara ) Province

Madagascar

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Andranondambo

Tuléar (Toliara) Province

Madagascar

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Betroka

Tuléar (Toliara) Province

Madagascar

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Chimwadzulu Hill

Ntcheu

 

Malawi

Joel Arem, Color Encyclopedia of Gemstones, 1987

Corundum-Sapphire

Kyauk Kyi

Singu

 

Myanmar

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Kyauksaikan

Singu

 

Myanmar

Gems & Gemology 2000 winter p315

Corundum-Sapphire

New-Yan

Singu

 

Myanmar

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Panhka

Mansi

Kachin State

Myanmar

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Nanyazeik (Nayazeik; Naniazeik)

Myitkyina district

Kachin State

Myanmar

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Thabeitkyin

Irrawaddy river

Mandalay

Myanmar

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Mogok

Mandalay

Myanmar

Joel Arem, Color Encyclopedia of Gemstones, 1987

Corundum-Sapphire

Dawna Hills

Hlaingbwe River Valley

Sagaing Division

Myanmar

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Momeik

Shan State

Myanmar

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Mong Hsak River

Mong Hsak

Shan State

Myanmar

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Dhading

Ganesh Himal

Gandaki

Nepal

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Mabila

 

Nigeria

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Jemaa

Kaduna

Nigeria

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Batakundi

 

Pakistan

Gems & Gemology 2004 winter p343

Corundum-Sapphire

 

Cyangugu

 

Ruanda

Gems & Gemology 2000 winter p315

Corundum-Sapphire

 

Kedrovka

Primorskiy Kray

Russia

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Loch Roag

Isle of Lewis

Outer Hebrides

Scotland UK

Jackson, B. 1984. Sapphire from Loch Roag, Isle of Lewis, Scotland. J.Gemmol. 19,336-42

Corundum-Sapphire

 

 

 

Sri Lanka

Joel Arem, Color Encyclopedia of Gemstones, 1987

Corundum-Sapphire

Bibile

Badulla

Central Province

Sri Lanka

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Haputale

Badulla

Central Province

Sri Lanka

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Koslanda

Badulla

Central Province

Sri Lanka

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Lunugala

Badulla

Central Province

Sri Lanka

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Passara

Badulla

Central Province

Sri Lanka

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Avissawella

Kegalla

Central Province

Sri Lanka

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Matale

Matale

Central Province

Sri Lanka

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Maskeliya

Nuwara Eliya

Central Province

Sri Lanka

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Nawalapitiya

Nuwara Eliya

Central Province

Sri Lanka

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Talawakele

Nuwara Eliya

Central Province

Sri Lanka

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Hatton

Nuwara Elyia

Central Province

Sri Lanka

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Kuruwitenna

Nuwara Elyia

Central Province

Sri Lanka

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Elahera

Polonnaruwa

Central Province

Sri Lanka

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Kalahagala

Polonnaruwa

Central Province

Sri Lanka

Gems & Gemology 2000 winter p315

Corundum-Sapphire

Kaluganga Valley

Polonnaruwa

Central Province

Sri Lanka

Gems & Gemology 2000 winter p315