Cobblestone & Stone Characteristics

History

• Historically, cobblestones were gathered from river beds as well as river banks during the 15th century, for use in paving over dirt streets in Europe, according to Paver Search. Americans used them in Boston, Chicago, New York and Pittsburgh in the early 20th century.

Cobblestone

• Cobblestone is the term given to rock when it has been physically weatherized into a small, rounded stone. It started out much bigger --- like a boulder-sized rock --- but has been honed down by nature's elements over many years. This type of stone is derived from sedimentary rock. Current stone manufacturers recreate cobblestone looks, in a variety of colors, using tools to hone it into shapes previously created by nature.

  The physical characteristics remain small and rounded and as strong as previous cobblestone, as the current rocks are typically created from granite or other hard, sturdy rock. Nature produced stones differ in overall stone coloration from stone to stone. Current products on the market do not vary; they seek a more consistent color look.

Other Stones

• Natural stones can be broken down into three major groups according to geological classification: igneous, sedimentary and metamorphic. Characteristics of each stone type are based upon how they are initially formed. Sedimentary rocks, of which cobblestone is one type, can be created in four different ways, thus producing different characteristics.

Igneous Stones

• Igneous rocks develop due to molten material --- such as lava --- cooling and crystallizing and contain the mineral silica. Stones, including granite, which contain silica are stronger and more durable than stones such as limestone, which contain softer minerals known as "carbonates."

Sedimentary Stones

• Sedimentary stones can contain either silica or a carbonate mineral. Sedimentary rocks with silica include cobblestones, sandstone and cantera. Sedimentary rocks with carbonate, a softer mineral, include coralstone, limestone and travertine; these stones' characteristics can range from very fragile to durable only under certain conditions and for certain uses.

Metamorphic Stone

• Metamorphic stones evolve from the softer mineral rocks, such as shale, which are more fragile, into stronger rocks that are more durable, like slate. They do this as a result of the process of temperature and pressure, which changes them. Hence, limestone metamorphic stones can change into marble stones, replete with varying multi-colors.