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.
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||Plutonic Granite|
|Age||more than 600 million years (Pre-Cambrian)|
|Colouring minerals:||Red-brown, Alkali 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.
A black-brown cordieritefels with big, shapeless, brown-red feldspar crystals.
Petrology: Dark red-brown, very coarse crystalline alkali feldspar, red colours along the gap cracks. The dark background is brown feldspar, black biotite and amphibole. Quartz appears in transparent grains.
Petrogenesis: This rock is from the Pre-Cambrian mountain range of the Indian sub-continent. There melts intruded into the earth crust and solidified in a depth of several kilometres under the surface. The erosion processes since then uncovered the basic mountain range and made the originally lower levels of the earth crust available for quarrying.