Primary Malachite forms an intriguing specimen of stalactites of fibrous crystals, with rounded tops.

Malachite | ‪#‎Geology

Formula: Cu2(CO3)(OH)2
System: Monoclinic
Colour: Bright green, with ...
Hardness: 3½ - 4
Streak: Light green

Malachite is a green, very common secondary copper mineral with a widely variable habit. Typically it is found as crystalline aggregates or crusts, often banded in appearence, like agates. It is also often found as botryoidal clusters of radiating crystals, and as mammillary aggregates as well.

From Mashamba West Mine DR Congo (Zaire)