Ripple Rock Gem and Mineral Club

Mohs Extended Scale

  • Plastic - 1
  • Graphite - 1
  • Talc - 1
  • Pencil Lead - 1
  • Sulfur - 1.5 - 2.5
  • Gypsum - 2
  • Alabaster - 2
  • Rock Salts - 2
  • Plaster of Paris - 2
  • Mercury - 2 - 2.5
  • Salt - 2 - 3
  • Amber - 2.5
  • Ivory - 2.5
  • Fingernail - 2.5
  • Pearl - 2.5
  • Zinc - 2.5
  • Gold - 2.5 - 3
  • Silver - 2.5 - 3
  • Aluminum - 2.5 - 3
  • Jet - 2.5 - 3
  • Copper Penny - 3
  • Calcite - 3
  • Limestone - 3
  • Shells - 3
  • Bronze - 3
  • Coral - 3
  • Barite - 3 - 3.5
  • Malachite - 3.5 - 4
  • Azurite - 3.5 - 4
  • Fluorite - 4
  • Platinum - 4 - 4.5
  • Iron - 4 - 5
  • Meteorite - 4.5
  • Palladium - 4.75
  • Apatite - 5
  • Tooth Enamel - 5
  • Lapis - 5 - 5.5
  • Obsidian - 5 - 5.5
  • Hematite - 5 - 6
  • Knife Blade - 5.5
  • Opal - 5.5 - 6
  • Turquoise - 5.5 - 6
  • Magnetite - 5.5 - 6.5
  • Rhodonite - 5.5 - 6.5
  • Titanium - 6
  • Rhodium - 6
  • Feldspar - 6
  • Orthoclase - 6
  • Rutile - 6 - 6.5
  • Fire Opal - 6 - 6.5
  • Moonstone - 6 - 6.5
  • Marcasite - 6 - 6.5
  • Iron Pyrite - 6.5
  • Tanzanite - 6.5
  • Nephrite - 6 - 7
  • Jade - 6 - 7
  • Glass - 6 - 7
  • Cassiterite - 6 - 7
  • Iridium - 6.5
  • Kunzite - 6.5 - 7
  • Peridot - 6.5 - 7
  • Bloodstone - 7
  • Quartz - 7
  • Rose Quartz - 7
  • Smokey Quartz - 7
  • Milk Quartz - 7
  • Black Opal - 7
  • Flint - 7
  • Aventurine - 7
  • Ametrine - 7
  • Agate - 7
  • Chalcedony - 7
  • Citrine - 7
  • Jasper - 7
  • Onyx - 7
  • Carnelian - 7
  • Amethyst - 7
  • Tiger's Eye - 7
  • Garnet - 7 - 7.5
  • Rhodolite - 7 - 7.5
  • Iolite - 7 - 7.5
  • Tourmaline - 7 - 7.5
  • Steel File - 7 - 8
  • Zircon - 7.5
  • Tungsten - 7.5
  • Morganite - 7 - 8
  • Beryl - 7.5 - 8
  • Aquamarine - 7.5 - 8
  • Emerald - 7.5 - 8
  • Spinel - 8
  • Topaz - 8
  • Smokey Topaz - 8
  • Blue Topaz - 8
  • Yellow Topaz - 8
  • Chrysoberyl - 8.5
  • Alexandrite - 8.5
  • Cat's Eye - 8.5
  • Cubic Zirconia - 8.5
  • Chromium - 8.5
  • Tungsten Carbide - 8.5 - 9
  • Corundum - 9
  • Sapphire - 9
  • Ruby - 9
  • Carborundum - 9 - 9.5
  • Moissanite - 9.25
  • Fullerite - 10-
  • Diamond - 10
  • Nanorods - 10+

The Mohs scale is a system of testing the hardness of a mineral, designed by Friedrich Mohs in 1812. Mohs was a mineralogist from Germany who wanted a simple way of testing the “scratching” ability of each mineral. What the mineral could scratch, or what could scratch the mineral determines its position on the Mohs scale.

Mohs designed the Mohs scale to work with relatively ordinary devices. For example, one tested the hardness of a mineral with things like a fingernail, a penny, glass, or a knife. Even having access to only a few of these things in the field could help determine a mineral’s placement on the Mohs scale.