Mist sandstone tiles & pool copping in honed from S & N Brothers
Sandstone is a sedimentary rock composed mainly of mineral grains.
Most sandstone is composed of quartz and / or feldspar because these are the most
common minerals in the Earth's crust. Like sand, sandstone may be any color, but
the most common colors are tan, brown, yellow, reds, grays, whites and black.
Sandstones are clastic in origin (as opposed to organic, like chalk and coal, or
chemical, like gypsum). They are formed from cemented grains that may either be
fragments of a pre-existing rock or be mono-minerallic crystals. The cements binding
these grains together are typically calcite, clays and silica. Grain sizes in sands
are in the range of 0.1 mm to 2 mm.
Formation of sandstone involves two principal stages. First, a layer or layers of
sand accumulates as the result of sedimentation, either from water (as in a river,
lake, or sea) or from air (as in a desert). Typically, sedimentation occurs by the
sand settling out from suspension. Finally, once it has accumulated, the sand becomes
sandstone when it is compacted by pressure of overlying deposits and cemented by the
precipitation of minerals within the pore spaces between sand grains. The most common
cementing materials are silica and calcium carbonate, which are often derived either
from dissolution or from alteration of the sand after it was buried. Colors will
usually be tan or yellow (from a blend of the clear quartz with the dark amber feldspar
content of the sand). A predominant additional colorant is iron oxide, which imparts
reddish tints ranging from pink to dark red (terra cotta), with additional manganese
imparting a purplish hue. Deposition from sand dunes can recognized by irregular and
fluidly shaped weathering patterns and wavy coloration lines when sectioned, while
water deposition will form more regular blocks when weathered. The regularity of the
latter favors use as a source for masonry, either as a primary building material or
as a facing stone, over other construction.
For further information contact:
S & N Brothers
phone: 02 9793 2001
fax: 02 9793 2002
web: www.snb-stone.com
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