Pedras - a Natureza pintou os lírios de Van Gogh no seu profundo céu nocturno e fechou o infinito no finito

Photo Credit  R.Weller/Cochise College.
Gemstones courtesy of Starborn Creations
Sedona. Arizona
www.geologyin.com


Malachite 

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.

Azurite

Formula: Cu3(CO3)2(OH)2

System: Monoclinic
Colour: Azure blue, blue, light ...
Lustre: Vitreous
Hardness: 3½ - 4
A secondary copper mineral frequently found in the oxidized zones of Cu-bearing ore deposits.