Crystal Cinnabar

Crystal Forms 
and Aggregates

Crystals are usually in thick tabular form with modified faces. Crystals are often integrown or twinned in penetration twins. Also as elongated rhombohedrons, in six-pointed star-shaped twins, and in complex crystal forms. Also massive, granular, in veins, in small ball-shaped aggregates, encrusting, and globular. Crystals are often striated.
 

Transparency

Transparent to opaque

Specific Gravity

8.0 - 8.1

Luster

Adamantine, submetallic, dull

Cleavage

1,3

Fracture

Uneven

Tenacity

Brittle to slightly sectile

Other ID Marks

Cinnabar crystals are birefringent, though transparent crystals are often too small or embedded in a matrix for this property to be properly observed.
 

In Group

Sulfides; Simple Sulfides

Striking Features

Color, heaviness, and low hardness.

Environment

In volcanic, mercury-rich deposits usually associated with hot springs. Also in epithermal veins.
 

Rock Type

Igneous, Metamorphic

Popularity (1-4)

2

Prevalence (1-3)

3

Demand (1-3)

1