![labradorite crystal from Finland with the phenomenon of blue labradorescence](https://www.patrickvoillot.com/wp-content/uploads/2021/03/labradorite-cristal-labradorescence141-150x150.png)
![ilvaite pear cut](https://www.patrickvoillot.com/wp-content/uploads/2021/03/ilvaite-poire4-300x200.png)
ilvaite
![ilvaite crystal from Mongolia, China](https://www.patrickvoillot.com/wp-content/uploads/2021/03/ilvaite-cristal-chine-300x200.jpg)
ilvaite crystal from Mongolia, China
Detailed sheet
ilvaite
Its name comes from the ancient name of Elba in Italy (Ilva), where it was identified in 1811.
![](https://www.patrickvoillot.com/wp-content/uploads/2021/04/zoom-in.png)
![](https://www.patrickvoillot.com/wp-content/themes/astra-child/images/icon-image.png)
CHEMICAL CHARACTERISTICS
(Ca,Fe3) [Si2O7] O(OH)
iron and calcium silicate
![](https://www.patrickvoillot.com/wp-content/uploads/2021/04/zoom-in.png)
![](https://www.patrickvoillot.com/wp-content/themes/astra-child/images/icon-image2.png)
PHYSICAL CHARACTERISTICS
Main color
black
Other colors
brown
very dark color, black with brown or greenish reflections
Color of streak
black
Luster
adamantine, metallic
Hardness
5.5 to 6.0
Density
3.95 to 4.00
Cleavage
good
Fracture
uneven
small flat portions on the cleavage
![](https://www.patrickvoillot.com/wp-content/uploads/2021/04/zoom-in.png)
![](https://www.patrickvoillot.com/wp-content/themes/astra-child/images/icon-image3.png)
OPTICAL PROPERTIES
Transparency
opaque
Refractive index
1.720 - 1.880
Double refraction
0.150
strong biaxial (+)
visible double refraction
No
Dispersion
+
Pleochroism
strong
Number of colors
3
green, yellow green, brown lights
Fluorescence
none
Inclusions
difficult to notice
![](https://www.patrickvoillot.com/wp-content/uploads/2021/04/zoom-in.png)
![](https://www.patrickvoillot.com/wp-content/themes/astra-child/images/icon-image4.png)
CRYSTALS PROPERTIES
prismatic with stripes
![](https://www.patrickvoillot.com/wp-content/uploads/2021/03/cristal-ilvaite.gif)
crystals system
orthorhombic
![](https://www.patrickvoillot.com/wp-content/uploads/2021/04/zoom-in.png)
![](https://www.patrickvoillot.com/wp-content/themes/astra-child/images/icon-image5.png)
OTHER INFORMATIONS
![](https://www.patrickvoillot.com/wp-content/uploads/2021/04/zoom-in.png)
![](https://www.patrickvoillot.com/wp-content/themes/astra-child/images/icon-image6.png)
APPROACHING GEMS
Exploited
sites
It is found on the island of Elba in Tuscany in Italy, in the Greek islands (Seriphos), at Dalnegorsk to Russia, in inner Mongolia in China.
use in jewelry
its dark color makes of it only a collection stone, sometimes faceted
Venez visitez
notre site web
voillot-joaillier.fr
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut elit tellus, luctus nec ullamcorper mattis, pulvinar dapibus leo.Lorem ipsum dolor sit amet, consectetur adipiscing elit. Ut elit tellus, luctus nec ullamcorper mattis, pulvinar dapibus leo consectetur adipiscing elit. Ut elit tellus, luctus nec.