The Moh’s hardness scale refers to scratch hardness. The resistance of one mineral to be scratched by another.
Friedrich Mohs (1773-1839), a Viennese mineralogist, introduced the term scratch hardness. The scale ranges from the softest at 1 through to the hardest at 10. Gemstones with a hardness of 1 and 2 are considered to be soft, from 3 to 5 medium, with 6 and over considered to be hard.
Because dust can contain quartz, it is important to realise that household dust can damage the lustre and brilliance of gemstones with a hardness below 7. Jewellery set with these stones should be well cared for to maintain their continued brilliance.
This table of Moh’s hardness lists gemstones by name alphabetically.
A B C – D E F G H – I J K L M N O P – Q R S T U V W X Y Z
| Gemstone | Hardness |
|---|---|
| Aegirine | 6 |
| Alexandrite | 8 ½ |
| Almandine | 7-7 ½ |
| Amazonite | 6-6 ½ |
| Amblygonite | 6 |
| Amethyst | 7 |
| Andalusite | 7½ |
| Andesine | 6-6 ½ |
| Anorthoclase | 6-6 ½ |
| Aquamarine | 7½-8 |
| Aventurine | 7 |
| Axinite | 6 ½ -7 |
| Benitoite | 6-6 ½ |
| Bytownite | 6-6 ½ |
| Bixbyite | 6-6 ½ |
| Boracite | 7-7 ½ |
| Cassiterite | 6-7 |
| Chalcedony | 6 ½ -7 |
| Chambersite | 7 |
| Chondroite | 6-6 ½ |
| Chromdravite | 7 |
| Chrysoberyl | 8½ |
| Chrysoprase | 6 ½ -7 |
| Citrine | 7 |
| Clinohumite | 6 |
| Clinozoisite | 6-7 |
| Cordierite | 7-7 ½ |
| Covellite | 1½ -2 |
