What is Mohs Scale? | Quality Granite & Marble

Quality Granite & Marble is located at 1123 S West St, Wichita, KS 67213


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Wichita Marble Countertops

What is Mohs Scale?

Interior Designer Countertop Program

Mohs scale of mineral hardness helps define the strength of minerals and natural stone, and is often referenced in countertop design and manufacturing. 

The scale is based on one stone or mineral’s ability to scratch another mineral. A very simple test, a rating is determined by taking one material and scraping it on another. If the material is able to produce a visible scratch on the other, it is considered harder. The scale was created by mineralogist, Friedrich Mohs in 1812.

Numbers are assigned to minerals based on their hardness. The higher the number, the harder the mineral is. While harder elements have since been discovered, Mohs original scale is still used as a guideline.

Mohs scale:

  • Talc – 1
  • Gypsum – 2
  • Calcite – 3
  • Fluorite – 4
  • Apatite – 5
  • Feldspar – 6
  • Quartz – 7
  • Topaz – 8
  • Sapphire – 9
  • Diamond – 10 

Using a very simple comparison of materials, the results have proven to be reliable, and the test is easy to conduct in the field. Mohs scale also includes items such as a fingernail, which has a hardness of 2.5; a copper penny (3.5) and a window’s glass (6.5).

Which the scale doesn’t directly relate to countertops, it is often a consideration for homeowners and designers who are concerned with countertop strength and scratch resistance. According to Mohs scale, popular countertop materials would be rated and ranked in this order:

  • Soapstone – 1
  • Marble – 3-5
  • Limestone – 3-5
  • Sandstone – 6-7
  • Granite – 6-8
  • Quartz – 7-8

Of course, keep in mind there are varying degrees of hardness and quality within each stone type. For example one slab of granite could be rated a 6 on Mohs scale, while another slab could be an 8. Also, there are many manufacturing methods and other factors involved in countertop production that determine the true hardness. Generally, Mohs scale is a good guide, however.

If you’re looking for a very durable countertop that is scratch resistant, quartz and granite are top choices for kitchen countertops, bars and bathroom vanities. 

If you have questions about natural stone countertops, or which stone is best for your project, give us a call: