Spirit Marble and Tile Care explain the great confusion surrounding the nature of Bluestone.
As the stone care company explains, Bluestone is not a geological term that falls into a category like that of Igneous, Sedimentary or Metamorphic. Bluestone, in reality, currently represents over 20 different rock types.
In the USA and Canada, Bluestone is generally a type of Sandstone, which is deep blue in colour. However, in some parts of the United States and Belgium, it is a form of Limestone that was formed in deeper waters and exposed to less light. This caused the Limestone to eventually fade from a deep blue to a light grey after long exposure in the sun.
In Australia, Bluestone comes in two forms. One type is commonly known as Victorian Bluestone, which is a form of Basalt. Basalt is an igneous rock made up mostly of feldspar and is usually grey to black and fine-grained due to rapid cooling of lava at the surface of the Earth.
In South Australia, Bluestone is known as a form of Slate. Slate is a metamorphic rock that is mainly made up of quartz and is usually pale grey or beige in colour. Compared to the Victorian Bluestone, the Bluestone Slate is less durable.
Then there is the Chinese Bluestone, which is commonly a grey Limestone. Limestone is a sedimentary rock that is mostly made up of minerals calcite and aragonite. Limestone is very porous and is highly reactive to acid.
Each type of Bluestone requires different methods of being treated and cared. Spirit Marble and Tile Care recommend asking suppliers about the supplied Bluestone as much as possible in order to help identify its characteristics and rock type. This information can range from the Bluestone’s place of origin, type of stone, porosity, any special laying procedures and whether it is acid sensitive.
For more information on Bluestone and Bluestone care, contact Spirit Marble and Tile Care.