Botallackite

Infobox mineral
name = Botallackite
category = ,
boxwidth =
boxbgcolor =


imagesize =
caption =
formula = Cu₂ [(OH)₃|Cl]
molweight =
color = Shades of green
habit =
system = Monoclinic
twinning =
cleavage = One, distinct to good
fracture =
tenacity =
mohs =
luster =
polish =
refractive = n_α= 1.775, n_β= 1.800, n_γ= 1.846
opticalprop =
birefringence = δ = 0.071
dispersion = r > v, strong
pleochroism = Weak
fluorescence=
absorption =
streak =
gravity =
density = 3.6
melt =
fusibility =
diagnostic =
solubility =
diaphaneity = Transparent to translucent
other =
references =

Botallackite, chemical formula Cu₂ [(OH)₃|Cl] is a secondary copper mineral, named for its type locality at the Botallack mine, St Just in Penwith, Cornwall. It is polymorphous with Atacamite, Paratacamite and Clinoatacamite. [http://www.mindat.org/min-732.html Mindat information page for Botallackite] ]

In the monoclinic crystal system, Botallackite is mountain-green to green in colour, with one distinct to good cleavage.

Botallackite forms in copper deposits exposed to weathering and salt water.

References