1, form: Slate is a sedimentary rock formation with the same sand.
2, ingredients: mainly for silicon dioxide. Its characteristics can be acid. According to slate slate can be divided into three types of components:
(1) the carbonate rock: the pure silica content is less than 40%, the content of aluminium oxide, calcium oxide content of less than 10% less than 15%, the magnesium oxide content of less than 10%, iron oxide content of 3%-7%.
(2) clay-slate: composed primarily of sericite, illite, chlorite, kaolinite, clay minerals, which constitute over 80% slate mineral composition, its silica content is greater than 50%, aluminium oxide content greater than 12%, calcium oxide, magnesium oxide content of less than 10% is less than 5%, its iron trioxide content above carbonate rocks.
(3) carbon, silica stone: mineral composition between carbonate-type of clay-slate, and slate, due to the strong degree of silicon and silica content is high, the stone quite hard, darker.
3, properties: a weak acid.
4, structure, stone structure of the sheets or blocks, granules fine grain size between 0.9~0.001mm often aphanitic texture, more compact, and most are arranged rock cleavage is growing thickness uniformity, hardness, water absorption less. Their life expectancy is generally about 100 years. Slate color to monochrome. Example: grey, yellow, green, grey, green, blue, black, Maroon, red, purple, etc. Because of the color of a single pure decoration, people feel elegant and generous. Slate is no longer generally polished, natural shape, forming a natural beauty.
Therefore, sandstone and slate flower color is better than marble and granite, its decoration is also used for some places with rich cultural connotation.