Porphyry

Porphyry is a layered stone which is mainly used for making pavements, stair tiles and facade coverings. The color is usually reddish, greyish-violet, brown or whitish-yellow. Natural and split surface are the most commonly used, but it is possible to have it flamed, honed and polished.

The color of porphyry is rarely uniform - there is a dominating tone (gray or red are the most common) but there are almost always some tiles in a batch that have some stripes or spots of different colour. The buyer of porphyry must keep in mind that when a porphyry is labelled as red or gray, by that it is meant the most dominant colour.

A common characteristic of porphyrys is microporousity - on natural surfaces there can be small holes of size 1-2 mm, certain materials can have also 1-2 cm macroporousity.

Porphyry is a hard stone which is frost resistant and the polish is very durable.

Porphyry materials used in construction are igneous vulcanic rocks with similar composition to rhyolites. This means that porphyry has similar mineralogical composition to granite - mainly quartz and feldspar.

The most common origins for porphyry are Italy, Mexico and Argetina.