Marble is a relatively soft stone. In measurement of hardness, marbles are on the 3rd position out of 10-point scale. Marble is composed of calcium, as our teeth. If you bite something too hard, the tooth can break. If you eat too many sweets, losses will occur. The stone responds in the same way. If inappropriate chemicals are used on the surface of the stone, corrosion will cause losses in the stone. Below, we present the measurement stone hardness scale (MSHS). This is a guide developed in the 19th century, which makes it easier to assess strengths and weaknesses of the stone. For example, the softer stone requires less active chemicals and more frequent cleaning.
4. Quartz (granite)
5. Feldspar (granite)
8. Calcite (most marbles)
The aim of the MSHS is to determine the stone resistance to abrasion. When sand and other fine contaminants are harder than the surface, they will scratch and destroy the stone. For example, a piece of hard plastic has a hardness of 2.0.
It will not scratch # 3 calcite (marble). In contrast, a grain of sand with hardness of 6 scratches calcite # 3, but it does not damage # 7 quartz, which is granite. The harder the stone is, the more resistant it is to wear. External deposits, which are brought to the building, are usually with hardness from 3.0 to 7.0.