In 1812 the Mohs scale of mineral hardness was devised by the German mineralogist Frederich Mohs (1773-1839), who selected the ten minerals because they were common or readily available. The scale is not a linear scale, but somewhat arbitrary. Talcum powder. Plaster of paris. Gypsum is formed when seawater evaporates from the Earth’s surface.

Mohs Hardness Scale for Minerals, Gemstones and other objects or materials Here is a list of Mohs hardness for some minerals, gemstones, metals, and materials arranged in alphabetic …

The Mohs hardness scale measures a mineral's resistance to scratching. Find the traditional scale here and a chart of select gems ordered by hardness.

One of the most important tests for identifying mineral specimens is the Mohs Hardness Test. This test compares the resistance of a mineral to being scratched by ten reference minerals known as the Mohs Hardness Scale (see table below).

THE VILLAGES GEM MINERAL SOCIETY Mohs Hardness of Selected Gems and Minerals Mineral or Substance Mohs Scale Mineral or Substance Mohs Scale Obsidian (Volcanic Glass) 5 Ruby 9 Onyx 7 Rutile 6 to 6.5 Opal 5.5 to 6.5 Sapphire 9 Orthoclase 6 to 6.5 Sapphire Spinel 8 Pargasite 5 to 6 Sapphirine 7.5

The Mohs Scale of Hardness is a list of 10 minerals in order of hardness from 1 - 10 with 1 being the softest and 10 the hardest. Every mineral fits somewhere in this list. Minerals higher on the list will scratch minerals lower down. The list is a non-linear scale however: The difference in hardness between 8 (topaz) and 9 (corrundum) is ...

GEM AND MINERAL HARDNESS ABSOLUTE HARDNESS WWW.FAIRFAXANDROBERTS.COM.AU MINERAL CHEMICAL FORMULA 1 3 5 7 9 2 4 6 8 10 Light to dark green, brown, white, grey. Is the softest known mineral and can easily be crushed into a powder form. Colourless white; shades of grey, yellow, green, red, purple, blue, brown, black. Can be scratched with a ...

This chart provides a concise reference for the relative hardness of common gemstone varieties. This document lists 185 gemstone types and their corresponding Mohs hardness ratings. The Mohs hardness scale ranges from 1 to 10, with 1 being the softest and 10 being the hardest.

Hardness Mineral Composition Absolute Hardness Image Common Objects 1 Talc Mg 3 Si 4 O 10 (OH) 2 1 2 Gypsum CaSO 4 ·2H 2 O 2 fingernail 3 Calcite CaCO 3 9 penny 4 Fluorite CaF 2 21 ... 8 Topaz Al 2 SiO 4 (OH-,F-) 2 200 9 Corundum Al 2 O 3 400 10 Diamond C 1500 Mohs Scale of Mineral Hardness Chart. Author: Denise Meeks Created Date: 9/29/2016 8 ...

Mohs’ scale is a way of describing mineral hardness. The scale ranges from 1 (the softest) to 10 (the hardest) and each of the 10 numbers is represented by a certain mineral. Follow along the lines to work out the order of minerals. The lines for diamond (the hardest mineral) and gypsum (a soft mineral) are both missing; can you draw them in ...