Sapphire Centre
How Should You Care for a Sapphire?
How to clean, wear and store sapphire jewellery safely, including the extra care rules for fracture-filled, diffusion-treated and star sapphires.
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Hardness Comparison
Compare scratch resistance across the gemstones profiled on this platform. Hardness is one durability factor among several, but it decides how a stone stands up to everyday dust and contact.
Compare two stones
Ceylon Sapphire
Corundum
Mohs hardness
9
Very hard: well suited to daily wear, including rings.
Blue Sapphire
Corundum
Mohs hardness
9
Very hard: well suited to daily wear, including rings.
Mohs hardness measures scratch resistance only. Toughness (resistance to chipping and breaking) is a separate property: a harder stone is not automatically a tougher one.
All profiled gemstones by hardness
| Gemstone | Mineral | Mohs |
|---|---|---|
| Ceylon Sapphire | Corundum | 9 |
| Blue Sapphire | Corundum | 9 |
| Padparadscha Sapphire | Corundum | 9 |
| Pink Sapphire | Corundum | 9 |
| Yellow Sapphire | Corundum | 9 |
| White Sapphire | Corundum | 9 |
| Green Sapphire | Corundum | 9 |
| Purple Sapphire | Corundum | 9 |
| Star Sapphire | Corundum | 9 |
| Ruby | Corundum | 9 |
| Alexandrite | Chrysoberyl | 8.5 |
| Chrysoberyl | Chrysoberyl | 8.5 |
| Chrysoberyl Cat's Eye | Chrysoberyl | 8.5 |
| Spinel | Spinel | 8 |
| Topaz | Topaz | 8 |
| Aquamarine | Beryl | 7.5–8 |
| Tourmaline | Elbaite (most gem tourmaline) | 7–7.5 |
| Garnet | Garnet (a group of related silicate minerals, not a single species) | 6.5–7.5 |
| Moonstone | Orthoclase (feldspar) | 6–6.5 |
| Zircon | Zircon | 6–7.5 |
Values are the standard published ranges shown on each gemstone profile. Reference points: diamond is 10, corundum (sapphire and ruby) defines 9, and quartz, a common component of household dust, is 7.
Mohs hardness measures scratch resistance on an ordinal scale; it is not proportional (corundum at 9 is far closer to diamond in number than in reality) and says nothing about toughness or cleavage. Wearability notes are general guidance, not a promise about any individual stone.
About this tool
Method: Displays the standard published Mohs hardness ranges recorded on each gemstone profile in our encyclopedia, sorted and paired for comparison.
Limitations: Ordinal scale; no toughness, cleavage or stability information; ranges reflect standard references, not testing of your stone.
Sources: GIA: Sapphire Care and Cleaning (corundum = Mohs 9) · Mindat: corundum (Mohs reference species) · Gemstone Encyclopedia
Last updated: 24 July 2026. Runs entirely in your browser; nothing you enter is transmitted or stored.
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