Gemsdat
 

                Home            Gemstones

 

     

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

Benitoite

1.754

 

 

 

3.73

3.73

bluish violet

Dallas Gem Mine, San Benito County, California, USA

3.77ct

 

 

 

 

 

strong blue

inert

GIA Gem Database  33927

Benitoite

1.755

 

 

 

3.7

3.7

bluish violet

Dallas Gem Mine, San Benito County, California, USA

3.36ct

 

 

 

 

 

strong blue

inert

GIA Gem Database  33928

Benitoite

1.756

1.8

0.044

0.044

3.65

3.65

blue

 

0.19ct

 

 

 

 

 

intens blue

inert

ACAM Lab  965

Benitoite

1.757

1.804

0.043

0.047

3.65

3.8

blue to violetish blue

New Idria District, Benito County, California

cause of blue colour has not yet been determinated

1.802

1.804

1.757

1.759

 

strong blue

inert ; colourless: dull red

Gems & Gemology 1997 fall p166-187

Benitoite

1.757

 

 

 

3.69

3.69

dark violet

Dallas Gem Mine, San Benito County, California, USA

3.48ct

 

 

 

 

 

strong blue

inert

GIA Gem Database  35170

 

TABLES

Stone

RI min

RI max

Biref min

Biref max

Dens min

Dens max

ne min

ne max

no min

no max

Reference

Benitoite

1.75

1.814

0.047

0.047

3.61

3.69

 

 

 

 

Gemology Tools Professional 2010

Benitoite

1.754

1.805

0.042

0.048

3.64

3.8

 

 

 

 

Gemmo.eu 

Benitoite

1.755

1.804

0.047

0.047

3.65

3.67

 

 

 

 

John Sinkakas, Gemstone and mineral data book,1972 

Benitoite

1.756

1.804

0.044

0.047

3.64

3.68

1.800

1.804

1.756

1.757

http://www.geminterest.com 

Benitoite

1.756

1.804

0.047

0.047

3.61

3.68

1.802

1.804

1.756

1.757

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

Benitoite

1.757

1.804

0.047

0.047

3.61

3.67

 

 

 

 

Bestimmungstabellen für Edelsteine, Birgit Günther, 1981 

Benitoite

1.757

1.804

0.047

0.047

3.61

3.68

1.804

1.804

1.757

1.757

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

Benitoite

1.757

1.804

0.047

0.047

3.65

3.68

1.804

1.804

1.757

1.757

Gemmological Tables, Ulrich Henn, 2004 

Benitoite

1.757

1.804

0.047

0.047

3.64

3.68

 

 

 

 

http://www.gemmology.be 

Benitoite

1.757

1.804

0.047

0.047

3.64

3.68

1.804

1.804

1.757

1.757

Joel Arem, Color Encyclopedia of Gemstones, 1987 

Benitoite

1.757

1.804

0.047

0.047

3.65

3.68

 

 

 

 

Gems, R Webster, 5th edition 1994 

Benitoite

1 757

1 804

0.047

0.049

3.61

3.68

1.804

1.804

1.755

1.757

Tabellen zur Edelstein-Bestimmung, Pschichholz FGA, 1975 

 

CAUSE OF COLOUR

Stone

Colour

Cause of colour

Reference

Benitoite

blue

Because traces of Fe are found in benitoite, ideas proposed include the Fe²+ - Ti4+ or the Fe²+ - Fe³+ intervalance charge transfer

http://minerals.gps.caltech.edu/

Benitoite

blue

Fe²+-O-Ti4- charge transfer (not fully proven)

Gems & Gemology Summer 1988

 

MINERAL INCLUSIONS

Inclusion

Stone

Reference

actinolite

Benitoite

Gems & gemology 1997 fall p182

aegirine-augite

Benitoite

Gems & gemology 1997 fall p182

albite

Benitoite

Gems & gemology 1997 fall p182

apatite

Benitoite

Gems & gemology 1997 fall p182

diopside

Benitoite

Gems & gemology 1997 fall p182

djurleite

Benitoite

Gems & gemology 1997 fall p182

joaquinite

Benitoite

Gems & gemology 1997 fall p182

natrolite

Benitoite

Dr. W.F. Eppler, Praktische Gemmologie, 1984

neptunite

Benitoite

Gems & gemology 1997 fall p182

serandite

Benitoite

Gems & gemology 1997 fall p182

 

LOCALITIES

STONE

LOCALITIES

REFERENCE

Benitoite

 

San Benito County

California

USA

Joel Arem, Color Encyclopedia of Gemstones, 1987

 

CHEMICAL DATA

Stone

Colour

Locality

Reference

SiO2

Al2O3

MnO

MgO

FeO

TiO2

CaO

Na2O

V2O3

K2O

SrO

ZrO2

BaO

Benitoite

colourless

Diamond Jo, Arkansas

USA

Gems & Gemology 1997 Fall p184

43.52

0.29

0.03

 

0.15

17.9

 

0.23

 

0.01

 

1.16

36.7

Benitoite

blue

Diamond Jo, Arkansas

USA

Gems & Gemology 1997 Fall p184

43.55

0.22

0.04

 

0.04

18.47

 

0.22

 

0.2

 

0.33

36.21

Benitoite

pink

Diamond Jo, Arkansas

USA

Gems & Gemology 1997 Fall p184

43.49

0.21

0.03

 

0.01

18.99

 

0.18

0.34

0.13

 

0.08

36.36

Benitoite

blue

Gem mine, California

USA

Gems & Gemology 1997 Fall p184

43.1

0.2

 

 

0.05

19.51

0.1

0.13

0.003

 

0.004

0.016

37.23

Benitoite

colourless

Gem mine, California

USA

Gems & Gemology 1997 Fall p184

42.62

0.04

 

 

0.01

19.44

0.006

0.14

0.002

 

0.003

0.108

37.27

Benitoite

blue

Ohmi

Japan

Gems & Gemology 1997 Fall p184

41.05

 

 

0.16

0

19.82

0.12

0.27

 

 

 

1.77

36.78

Benitoite

blue

Ohmi

Japan

Gems & Gemology 1997 Fall p184

43.16

0.1

0.11

0.14

0.033

19.11

0.24

0.75

 

0.21

 

 

36.04

Benitoite

colourless

Ohmi

Japan

Gems & Gemology 1997 Fall p184

43.55

0.18

0.05

0.12

0.081

19.3

0.28

0.84

 

0.44

 

 

34.82

Benitoite

colourless

Victor claim, California

USA

Gems & Gemology 1997 Fall p184

43.66

0.3

0.03

 

0.01

19.29

0.11

0.2

 

 

 

 

36.48