Calsilica
Calsilica also knows as rainbow Calsilica. It can be a gem that is opaque colorful stripes/layers of light and dark blue, green, yellowish, orange, red, black colored and occasionally even pink. Calsilica is a treasure that is popular is easily obtainable as cabochons and carvings.
Rainbow Calsilica is a relatively rare new stone from Mexico. It has been claimed that Calsilica is just a normal form of microcrystalline Calcite with layers of various clay that is normal as the bonding and coloring agents. It is claimed to be mine in Chihuahua, Mexico where it was presumably discovered within the veins or seams of volcanic rhyolite in the mine. Although suppliers claim that Rainbow Calsilica is just a stone that is natural tests have indicated that it’s powdered carbonate rock artificially colored and then stabilized with plastic. It contains an assortment of Calcite, silica, plastic and artificial coloring pigments such as PB15, an art-supply pigment, and a material that is paraffin-like. [ref: Winter 2002, Gems and Gemology, a journal of the Gemological Institute of America].
In 2003, the Swiss Gemological Institute ( www.SSEF.ch ) published an article on Calsilica inside their publication. SSEF purchased two specimens at a mineral show in France in 2002. The seller produced photographs for the mine that is alleged Mexico along with a verification letter from a US laboratory stating that the materials were not man-made. SSEF’s assessment unearthed that the base materials that are white certainly Calcite. However, they also discovered coloring that is man-made within the specimens. and that the particles were bonded together by a transparent soft, plastic-like material that was really similar to paraffin wax.
| Chemical Formula: | CA(CO3) + man-made coloring pigments and bonding agents |
| Calcium Carbonate (Calcite) + man-made coloring pigments and bonding agents | |
| Crystallinity: | Aggregate |
| Colors: | Blue, Green, Yellow, Orange, Red, Black Stripes |
| Transparency: | Opaque |
| Specific Gravity: | 1.88-1.92 |
| Fluorescence: | SWUV: Variable LWUV: Variable |
| Pleochroism: | None |
| Cleavage: | None |
