Gemsdat
 

                Home            Gemstones

 

      

INVESTIGATIONS

Stone

RI min

RI max

Dens min

Dens max

Colour

Location

Info

Spectrum

UVS

UVL

Reference

Magnetite - spinel group

 

 

4.64

5.11

 

Den Chai en Bo Phloi, Thailand

strong magnetic, Den Chai: 86% magnetite+10% ulvöspinel; Bo Phloi: 48% magnetite +33% ulvöspinel

 

inert

inert

The Australian Gemmologist 2008 Vol 23, N°6, p242-253

 

TABLES

Stone

RI min

RI max

Dens min

Dens max

Reference

Magnetite

2.42

2.42

4.9

4.9

Gemmological Tables, Ulrich Henn, 2004 

Magnetite

 

 

5.17

5.17

Gems, R Webster, 5th edition 1994 

Magnetite

2.42

2.42

5.1

5.2

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

 

CAUSE OF COLOUR

 

MINERAL INCLUSIONS

 

LOCALITIES

 

CHEMICAL DATA (%)

Stone

Colour

Locality

Reference

SiO2

Al2O3

MnO

MgO

FeO

TiO2

CaO

Na2O

Fe2O3

Magnetite

black

Den Chai

Thailand

The Australian Gemmologist 2009,Vol 23, N°6 p244

0.58

4.71

0.5

0.31

34.37

3.26

0.12

 

55.6

Magnetite

black

Den Chai

Thailand

The Australian Gemmologist 2009,Vol 23, N°6 p244

0.61

4.53

0.35

0.47

32.95

3.27

 

0.38

57.39

Magnetite

black

Bo Phloi

Thailand

The Australian Gemmologist 2009,Vol 23, N°6 p244

0.38

8.31

0.44

3.7

38.02

12.33

 

 

35.87

Magnetite

black

Bo Phloi

Thailand

The Australian Gemmologist 2009,Vol 23, N°6 p244

0.42

6.58

0.44

2.78

37.72

12.96

 

0.49

37.8