Gemstone Hardness Comparison

	Mineral used for comparison	Simple Hardness	Hardness
1	Diamond		140,000.00
2	Ruby, Sapphire, Alexandrite, Chrysoberyl		1,000.00
3	Aquamarine, Emerald, Morganite, Spinel, Topaz		175.00
4	Amethyst, Citrine, Garnet, Iolite, Kunzite, Peridot, Tanzanite, Tourmaline, Zircon	Scratches window glass	120.00
5	Diopside, Lapis lazuli, Orthoclase, Turquoise	Can be scratched with a steel file	37.00
6	Apatite, Obsidian, Sphene, Glass	Can be scratched with a knife	6.50
7	Coral, Fluorite, Pearl	Can easily be scratched with a knife	5.00
8	Calcite, Ivory	Can be scratched with a copper coin	4.50
9	Amber, Gypsum	Can be scratched with a fingernail	1.25
10	Talc	Can be scratched with a fingernail	0.03