The rock these grew in was once a seafloor.
The Moroccan azurite workings cut into a hard dolomite of Triassic to Early Jurassic age, and the copper carbonates crystallised into voids inside it. Collectors working the same rock have found small brachiopods, shelled marine animals, in among the specimens.
So the sequence runs: a shallow sea, then a limy seafloor hardened into dolomite, then copper-bearing water moving through the cavities left behind, tens of millions of years later, dropping blue and green crystals into holes that used to hold shellfish. The site has been worked for specimens since the 1960s.
Azurite alters to malachite in heat or damp, so keep this somewhere dry and stable and out of direct sun. Copper carbonates are toxic if swallowed. Dust rather than wash, keep it away from children and pets, and wash your hands after handling.
Mineral: Azurite (Cu₃(CO₃)₂(OH)₂) with malachite (Cu₂(CO₃)(OH)₂), both copper carbonates
Crystal system: Both monoclinic
Origin: Morocco
Hardness: 3.5 to 4 on the Mohs scale for both; soft and brittle, handle by the matrix
Treatment: None
Dimensions: 5.18 x 3.22 x 5.57 cm
Weight: 76.63 g
You will receive the exact piece photographed.