Stone

RI min

RI max

Biref min

Biref max

Dens min

Dens max

Colour

Locality

Info

nx min

nx max

ny min

ny max

nz min

nz max

Spectrum

UVS

UVL

Reference

Prehnite

1.61

1.632

0.022

0.022

2.9

2.9

yellow

11.14ct, transparent

none

brownish yellow

brownish yellow

ACAM Lab 

Prehnite

1.61

1.63

0.02

0.02

2.94

2.94

greenish yellow

Australia

8.56ct

no features

inert

inert

GIA Gem Database  35486

Prehnite

1.612

1.642

0.03

0.03

2.99

2.99

yellow

0.5ct, transparent

1.612

1.612

1.622

1.622

1.642

1.642

inert

inert

ACAM Lab  880

Prehnite

1.615

1.64

0.025

0.025

3.01

3.01

greenish yellow

West Paterson, New Jersey, USA

11.10ct

no features

inert

inert

GIA Gem Database  35208

Prehnite

1.617

1.639

0.022

0.022

2.91

2.96

greenish yellow

Merelani, Tanzania

weak yellow

inert

Gems & Gemology 2007 Spring p60

Prehnite

1.617

1.645

0.026

0.026

2.92

2.93

light to medium greyish green and yellow

Mali

1.617

1.619

1.643

1.645

inert

inert

Gems & Gemology 2006 summer, p178-179

Prehnite

1.618

1.641

0.023

0.023

2.91

2.91

greenish yellow to yellow

Wave Hill, Northern Territories, Australia

semitransparent to translucent

none

weak orange

weak dull yellow

Gems & Gemology 2001 spring, p71

Prehnite

1.618

1.638

0.02

0.02

2.91

2.91

greenish yellow

Australia

10.55ct, translucent

inert

inert

GIA Gem Database  35485

Prehnite

1.618

1.65

2.9

2.9

greenish yellow

Australia

15ct, translucent

none

inert

inert

ACAM Lab  1876

Prehnite

1.62

1.62

2.87

2.92

greyish yellowish green

chatoyant cabochons, 4.95 - 5.40 ct, spot RI

Gems & Gemology 2007 Spring, p72

Prehnite

1.63

1.652

0.022

0.022

2.96

2.96

greyish green

13.61ct, translucent

inert

inert

GIA Gem Database  35468

Prehnite

1.63

1.65

0.02

0.02

2.96

2.96

light bluish green

South Africa

15.18ct

no features

inert

inert

GIA Gem Database  35467

Stone

RI min

RI max

Biref min

Biref max

Dens min

Dens max

nx min

 nx max

ny min

ny max

nz min

nz max

Reference

Prehnite

1.61

1.64

2.8

2.95

John Sinkakas, Gemstone and mineral data book,1972 

Prehnite

1.61

1.673

0.02

0.036

2.8

2.95

1.610

1.637

1.615

1.647

1.632

1.673

Gemmological Tables, Ulrich Henn, 2004 

Prehnite

1.61

1.646

0.03

0.031

2.8

2.95

1.610

1.615

1.640

1.646

Tabellen zur Edelstein-Bestimmung, Pschichholz FGA, 1975 

Prehnite

1.61

1.673

0.02

0.033

2.8

3

1.610

1.637

1.615

1.650

1.632

1.673

http://www.geminterest.com 

Prehnite

1.61

1.64

0.03

0.03

2.8

2.95

Gems, R Webster, 5th edition 1994 

Prehnite

1.61

1.666

0.02

0.034

2.8

2.96

Gemmo.eu 

Prehnite

1.611

1.669

0.03

0.039

2.82

2.94

Bestimmungstabellen für Edelsteine, Birgit Günther, 1981 

Prehnite

1.611

1.669

0.021

0.039

2.8

3

1.611

1.632

1.632

1.669

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

Prehnite

1.611

1.665

0.021

0.033

2.8

3

http://www.gemmology.be 

Prehnite

1.611

1.665

0.021

0.033

2.8

3

1.611

1.632

1.615

1.642

1.632

1.665

Joel Arem, Color Encyclopedia of Gemstones, 1987 

Prehnite

1.611

1.665

0.021

0.033

2.8

3

1.611

1.632

1.615

1.642

1.632

1.665

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

Prehnite

1.614

1.665

0.02

0.031

2.85

3

Gemology Tools Professional 2010

Prehnite

Wave Hill

Northern Territory

Australia

Gems & Gemology 2001 spring, p71

Prehnite

Mali

Gems & Gemology 2006 summer, p178-179

Prehnite

Mawaya pit, Merelani Hills (Mererani), Umba Valley

Lelatema Mts

Arusha Region

Tanzania

Gems & Gemology 2007 Spring p60