porphyry
- Scope note
- A dark purplish-red rock, first quarried in ancient Egypt, containing relatively large crystals in a fine-grained igneous matrix. One of the hardest rocks, it takes a high polish and is valued as a durable sculptor's material and as a decorative architectural material. It is considered the best material for the muller and slab used for grinding artists' colors.
- Date of creation: 29-Apr-2024
Accepted term: 29-Apr-2024