Porphyry is a very hard extrusive igneous rock consisting of large-grained crystals, such as feldspar or quartz, dispersed in a fine-grained feldspathic matrix or groundmass. The groundmass may have invisibly small crystals or the individual crystals may be easily distinguished as in granite. Porphyry refers to the "texture" of igneous rocks (just as "satin" refers to a type of fabric rather than the fiber it's made from).

Porphyry deposits are formed when a column of rising molten magma is cooled in two stages. In the first stage, the magma is cooled slowly deep in the earth's crust, creating the large crystal grains. In the final stage, the magma is cooled rapidly at a relatively shallow depth or as it erupts from a volcano.

Porphyry granite cobblestones are available in sizes 4" x 4" with a thickness of 1" to 3" depending on the project requirement. Other cobblestone sizes and random lenths cut to size are also available.

Minimum delivery is one container or truckload. A 20ft container of 4" x 4" at 1" to 2" thickness will cover aproxiamtely 2,000+ sq ft. Installation in a mortar bed is recommended.

Because there is little or no maintenance required, porphyry granite cobblestones have, for many years, been an important paving material in Europe. If you are watching the winter Olympics from Torino look at the roads and piazzas of the city.

Porphyry granite cobblestones have a naturaly split faced slip resistant surface that is not attacked by salt or gasoline residue. This makes it an appropriate use where harsh winter conditions exist.

The advantage of porphyry granite cobblestones is their potential for design configuration. The cobblestones can be arranged in unique geometric patterns (circular, angular and arched). In some projects, marble cubes are combined with porphyry granite cobblestones cubes to highlight a specific artistic design.