Minerals as Gems
 Diamond |  Ruby |  Emerald |  Sapphire |
 Smoky Quartz |  Citrine Quartz |  Ametrine Quartz |  Clear Quartz |
 Amethyst |  Rose Quartz |  Beryl |  Aquamarine |
 Labradorite |  Diopside |  Enstatite |  Topaz |
 Forsterite |  Ferroaxinite |  Zircon |  Scapolite |
 Marialite |  Orthoclase |  Andalusite |  Sillimanite |
 Epidote |  Calcite |  Zoisite |  Spodumene |
 Fluorite |  Rhodochrosite | Zoisite | Spodumene |
It is traditional to measure the size of gems in carats.
| Minerals |
| HyperPhysics*****Geophysics | R Nave |