In 1801 Mr. Mohs moved to the country of Austria. One of his jobs there was as the curator of a private mineral collection that was owned by a banker named J.F. van der Null. (a “curator” is a person who takes care of a collection of some kind.)
Mr. van der Null wanted his collection to be organized into categories. He also wanted Mohs to identify the many unknown minerals in his collection.
Believe it or not, in the early 1800’s no one had created a system for identifying minerals. So, Mr. Mohs started to study the different physical properties of minerals as a way to identify them. He noticed that some minerals are very soft, others are extremely hard. He also observed that harder minerals could scratch softer ones. With this in mind, Friedrich Mohs decided to develop a scratch test where he could determine the hardness of a mineral. To make his scratch test more accurate and helpful, he carefully observed many minerals and created a list of 10 minerals that he arranged from softest to hardest.
The scale is a list of minerals arranged from softest (No. 1) to hardest (No. 10) which is used to determine the hardness of all other minerals.
Mohs’ Scale of Hardness:
- Orthoclase Feldspar
The mineralogist who created this scale was named Friedrich Mohs.
To this very day, we know this list as “Mohs’ Scale of Hardness.”