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Popular Hard Surfaces & Their Hardnesses

Frequently on the Internet you will find articles that refer to the "hardness" of a specific material. Some materials and/or articles will even make mention of the Mohs Scale of Mineral Hardness. In fact, we reference that popular scale of measuring how hard a stone is frequently.

In virtually all cases the reason for the reference is in the contaxt of talking about a material that does not appear on that scale. To make referencing easier, we have put together this table of surface material hardness. This table lists many of the most popular hard materials used in construction, architecture, and building projects along with each material's Mohs scale hardness. Additionally, the table includes some remarks about each material.

Surface Material Hardnesses
Surface Material Hardness On Mohs Scale Remarks
Granite 6-7 Because granite varies in the porosity and composition, the hardness is a range; usually from 6 to 7.
Quartz 7 Quartz is an engineered material using polymer resins and is consistently around 7 on the Mohs scale.
Marble 3 Marble is made up of various substances but the primary mineral is calcite which is a soft material.
Quartzite 7 Being a natural stone that is primarily composed of the natural mineral quartz, quartzite is a very hard material.
Limestone 2-3 Like marble, limestone is a material that is composed of calcite. Therefore, it too falls on the soft end of the Mohs scale.
Soapstone 2-3.5 Although soapstone contains schist, it also has a large amount of talc (which is on the bottom end of the scale of the Mohs scale).
Slate 5-6 Slate is composed of various minerals with varying hardnesses. One of the main minerals is quartz, so it is no wonder it's in the middle of the scale.
Travertine 3-4 Travertine is a specific type of limestone that forms in a specific manner and is composed largely of calcite, making it softer than others.
Porcelain Approx. 7 Porcelain is a man made material that is created using intense heat and pressure, making it a hard material like others in this table.
Sintered Stone 7-8 Sintered stone is made by super heating and pressurizing raw minerals, a process known as "sintering". It registers very high on the scale.
Concrete 5-7 Depending on how the concrete is purposed and what it contains, it can range from 3-8. Most U.S. concrete though ranges from 5-7.