Terlinguaite

Terlinguaite is the naturally occurring mineral form of Mercury oxychloride formula Hg2ClO. It is formed by the weathering of other mercury containing minerals. Discovered in 1900 in the Terlingua District of Brewster County, Texas for which it is named. Its color is yellow, greenish yellow, brown or olive green.
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General Information:
 Chemical Formula:
Hg+Hg++ClO
 Composition:
(Molecular Weight = 452.63 gm)
Mercury 88.63 % Hg
Chlorine 7.83 % Cl
Oxygen 3.53 % O 
 Empirical Formula:
HgHgClO
 Environment:
Oxidized portions of mercury deposits.
 Locality:
Terlingua, Brewster Co., Texas, USA.
 Name Origin:
Named after its locality.
Physical Properties:
 Cleavage:
[101] Perfect
 Color:
yellow, greenish yellow, brown, or olive green.
 Density:
8.7
 Diaphaniety:
Transparent to translucent
 Habits:
Striated - Parallel lines on crystal surface or cleavage face., Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).,
 Hardness:
2-3 - Gypsum-Calcite
 Luminescence:
Non-fluorescent.
 Luster:
Adamantine
 Streak:
light yellow
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