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Classification of Malachite
IMA status:	Valid - first described prior to 1959 (pre-IMA) - "Grandfathered"
Strunz 8th edition ID:	5/C.01-20
Nickel-Strunz 10th (pending) edition ID:	5.BA.10 5 : CARBONATES (NITRATES) B : Carbonates with additional anions, without H2O A : With Cu, Co, Ni, Zn, Mg, Mn
Dana 7th edition ID:	16.3.2.1
Dana 8th edition ID:	16a.3.1.1 16a : ANHYDROUS CARBONATES CONTAINING HYDROXYL OR HALOGEN 3 : (AB)2(XO3)Zq
Hey's CIM Ref.:	11.2.1 11 : Carbonates 2 : Carbonates of Cu
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Occurrences of Malachite
Geological Setting:	It is the most common secondary mineral found in the oxidized zones of copper deposits.
Physical Properties of Malachite
Lustre:	Adamantine, Vitreous, Silky, Dull, Earthy
Diaphaneity (Transparency):	Transparent, Translucent
Colour:	Bright green, with crystals deeper shades of green, even vary dark to nearly black; green to yellowish green in transmitted light.
Streak:	Light green
Hardness (Mohs):	3½ - 4
Hardness Data:	Measured
Tenacity:	Brittle
Cleavage:	Perfect Perfect on {201}, fair on {010}.
Fracture:	Irregular/Uneven, Sub-Conchoidal, Fibrous
Density (measured):	3.6 - 4.05 g/cm3
Density (calculated):	4 g/cm3
Crystallography of Malachite
Crystal System:	Monoclinic
Class (H-M):	2/m - Prismatic
Cell Parameters:	a = 9.48Å, b = 12.03Å, c = 3.21Å β = 98°
Ratio:	a:b:c = 0.788 : 1 : 0.267
Unit Cell Volume:	V 362.52 ų (Calculated from Unit Cell)
Z:	4
Morphology:	Crystals uncommon, usually short or long prismatic or acicular, parallel to [001]; often grouped in rosettes, sprays, or tufts. Botryoidal to mammilary aggregates of radiating fibrous crystals more common. It may also be massive, compact, and stalactic.
Twinning:	Untwinned crystals are extremely rare. Typically twinned on {100}, sometimes as penetration or polysynthetic twinning with the axis parallel to [201].

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