Stone flaming or thermaling is the application of high temperature to the surface of stone to make it look like natural weathering. The sudden application of a torch to the surface of stone causes the surface layer to expand and flake off, exposing rough stone. Flaming works well on granite, because granite is made up of minerals with differing heat expansion rates.

Process

After removing a rock from a

quarry A quarry is a type of open-pit mine in which dimension stone, rock, construction aggregate, riprap, sand, gravel, or slate is excavated from the ground. The operation of quarries is regulated in some jurisdictions to reduce their envi ...

, the rock is sliced into multiple flat slabs using a diamond gang saw. The saw leaves flat surfaces with circular marks. Flaming is done by wetting, and then running an oxygen-acetylene or oxygen-propane torch over the surface. As shown in both pictures, the torch is usually held at a 45 degree angle to the stone, so that released glowing sand grains are blown away in a harmless direction.

Alternatives

Alternative techniques for creating a rough surface on sawed stone include: *

bush hammer A bush hammer, also known as an axe hammer, is a masonry tool used to texturize stone and concrete. The term is derived from the German word ''bosshammer'', where Old German ''bossen'' meant "to beat". Description and use Bush hammers exist in ...

ing *

sandblasting Sandblasting, sometimes known as abrasive blasting, is the operation of forcibly propelling a stream of abrasive material against a surface under high pressure to smooth a rough surface, roughen a smooth surface, shape a surface or remove su ...

* hydrofinishing

References

External links

Stone surfaces
photos of various surface treatments

photos of stone flaming
Understanding Flagstone: Sawcut, Thermaled, and Chiseled EdgesPhotos of hydrofinishing
{{Stonemasonry Stonemasonry

Process

Alternatives

See also

References

External links