Stones can have many aliases. This is due to language differences, supplier choice, coloquial trends or slang, or sometimes errors and ambiguity between rocks. Read more here.
|Braun Antico, Marrom Antik, Angola Brown|
Commercial classification sometimes differs to the scientific, geological designation. In particular, some limestones are deemed marble especially if they take a high polish. Read more here.
|Petrographic assignment||Anorthosite (Plutonite)|
|Age||1.5 Billion years (Pre-Cambrian)|
|Colouring minerals:||Dark brown Feldspar|
MOHS is the standard scale of hardness for minerals 1-10, with 10 being the MOHS of diamond. We also use the broad terms Hard and Soft for simplicity. Read more here.
Petrology:Anorthosite consists almost exclusively of Calcium rich Plagioclase Feldspar. A very coarse crystalline structure, with large dark brown crystals (upto 10cm) and fine hairline cooling cracks. Feldspar has a scratch resistance similar to steel.
Petrogenesis:Liquefied rocks rich in Calcium and containing Silicates cooled slowly in the earth’s crust, forming large crystals. Extreme pressure and displacement caused tearing and rupturing, evidenced by the visible hairline cracks that permeate the stone right through. This has no bearing on the technical properties of the material as over millions of years the stone has unified as a mineral.