Sandstone has been a popular building stone
for centuries. Its versatility and durable nature,
with its variety of earth tones and textures makes it a popular stone used for paving,
floors
and much more.
GROUP |
Sedimentary | ||
COMMON ROCK-FORMING MINERAL GROUP |
Siliceous | ||
COMPOSITION |
The main minerals are quartz, feldspar and mica with a variety of accessory minerals. These minerals may be cemented by silica, calcite or iron oxides. | ||
HARDNESS |
Medium to Hard | MOHS' SCALE | 4 - 7.5 |
POROSITY % |
0.5 - 35.0 | ABSORPTION % | 0.2 - 9.0 |
WEATHERING |
The types of cementing material and the presence of silt or clayey matter will determine how well the sandstone will weather in any given environment. Those cemented by silica and have a high quartz content are extremely resistant...Iron oxide cemented sandstone's weather well in dry climates. They become harder and stronger, resisting weathering and deterioration. The calcite cemented sandstone's are more easily weathered. When silt and clayey matter are present they form poor bonds and absorb water easily, this can be a cause of flaking and spalling. Also in colder climates the absorbed water freezes resulting in cracks and spalling. The surface of some sandstone's may not weather uniformly, there may be a lose of material by flaking, spalling, etc. in some areas and not in others because sandstone is formed in layers. Some of these layers may be more resistant due to their composition and if the surface is cleft, different layers are exposed all resulting in a differential weathering process. | ||
TENDENCIES |
Absorbs oils and other liquids easily. | ||
COLORS |
White to buff...Full range of earth tones to multi-colored banded pastels. | ||
FINISHES |
Natural Cleft Texture...Honed...The harder denser varieties will take a High Honed Finish. | ||
NOTATIONS |
Due to the high absorption factor it is highly recommended for practical maintenance considerations and to minimize staining, that the stone be treated with a water/soil and or oil repellent. | ||
Sandstone is predominantly
composed of consolidated quartz sand grains cemented
together. They
come from three primary formative environments, ancient shallow sea
beds, fresh water rivers and deserts. There are different varieties of sandstone's,
generally defined as "calcareous", the cementing agent being calcite, "quartzitic",
high quartz content cemented by silica also referred to as a "quartzite", this
is a
sedimentary rock and not to be confused with a "metamorphic quartzite", and
"arkosic", containing quartz and a notable quantity
of the mineral feldspar, the
cementing material is usually calcite or iron oxide.