01 / Geological family
Origin and composition
- Geological family
- Igneous
- Origin and composition
- vesicular basaltic scoria with alteration minerals
- Origin
- Lalibela, Ethiopia
- Appearance and identification
- reddish-brown, pink or dark grey tones
Igneous rocks form when molten material solidifies. Cooling underground can produce visible crystals, as in granite; cooling at the surface can produce fine grains, cavities or porphyritic textures. Basalt, granite and many porphyries illustrate different compositions and structures. The commercial term granite can also include other geological rock types: a specification benefits from both the trade name and petrographic description.
02 / History and curiosities
History and curiosities
The celebrated rock-hewn churches were carved directly into this volcanic material.
03 / Applications and design
Applications and design
Rock-hewn architecture and traditional masonry.
Finishes and processes ↗04 / Technical interpretation
What to ask your supplier
Do not assign the properties of dense basalt to porous scoria.
05 / Care and maintenance
Care and maintenance
Remove dust and grit with soft tools, wash with a compatible neutral cleaner, then rinse and dry. Identify composition before using stain or scale removers: carbonate stones are acid-sensitive. Test every treatment in an inconspicuous area. An impregnator can reduce absorption but does not make a material waterproof or stain-proof.
Thoughtful cleaning, protection and maintenance ↗07 / Sources and further reading
