|
Chemical formula
|
SiO 2 •nH 2 O |
|
Crystalline System
|
Amorphous |
|
Class
|
Silicates - Mineraloid |
| Origin | Madrid Spain |
| Size | 2.0-3.0cm |
Massive Silex in gray tones.
It has a composition similar to that of quartz, from which it differs because it has water molecules inside. They are very frequently found filling cavities of rhyolites or sedimentary rocks. There are numerous varieties of opal that have different appearances.
The mineral includes a label with the name and origin and is attached to a cardboard box. 4 cm square.
*The price is per unit (a single cardboard box of the four shown in the photo)
Since the minerals are natural, you will receive a piece similar to the one in the photograph. The minerals come in cardboard boxes and are glued to a porex base with hot silicone; These can be removed using ethyl alcohol without damaging the mineral. The size is approximate.