Mohs Hardness Scale
By Educational Resources
2021 (approx.)
![This image shows ten minerals from soft to hard and common tools used to test the hardness of each mineral.](https://d9-wret.s3.us-west-2.amazonaws.com/assets/palladium/production/s3fs-public/styles/full_width/public/thumbnails/image/Final_Mohs%20Hardness_R.%20Lugo.jpg?itok=rNfTBLQC)
Detailed Description
The Mohs Scale of Mineral Hardness (created by Friedrich Mohs in 1822)
https://pubs.usgs.gov/gip/gemstones/mineral.html
Sources/Usage
Public Domain.