Crystal Care

Gemstone Hardness Chart: The Mohs Scale for Every Stone

Whether a gemstone can survive daily life on your finger, or needs to be tucked safely in a drawer, comes down largely to one number: its hardness on the Mohs scale. It’s the single most useful fact to know before you buy a stone for a ring, store your collection, or clean anything — and yet it’s the thing most beginners overlook until a favorite piece picks up its first scratch.

This guide explains the Mohs scale in plain terms, gives you a full hardness chart for 60+ popular stones, and shows you how to use that number to make smart choices about jewelry and care. Bookmark it — it’s the kind of reference you’ll come back to every time you add a stone.

What Is the Mohs Hardness Scale?

The Mohs scale, created by mineralogist Friedrich Mohs in 1812, ranks a mineral’s resistance to scratching from 1 (softest) to 10 (hardest). Each mineral can scratch anything below it and be scratched by anything above it. Talc sits at 1, diamond at 10.

The scale isn’t evenly spaced — the jump from 9 (corundum, like sapphire) to 10 (diamond) is far larger than the steps lower down — but as a practical ranking for everyday use, it’s exactly what you need.

The most useful rule of thumb to remember: everyday dust contains quartz, which is a 7. That means any stone softer than 7 can slowly be scratched just by being wiped with a dusty cloth or rubbed during normal wear. It’s why a hardness of 7 or above is the rough cutoff for low-maintenance jewelry.

Hardness vs. Toughness (They’re Not the Same)

This trips up a lot of people, so it’s worth thirty seconds. Hardness is scratch resistance. Toughness is resistance to chipping, cracking, or breaking. They’re different properties.

Diamond is the hardest natural material (10) yet can chip if struck at the wrong angle. Jade is only about 6.5 but is exceptionally tough — historically carved into tools because it resists breaking. So a “hard” stone isn’t automatically unbreakable, and a softer stone isn’t automatically fragile. Hardness tells you about scratching; keep toughness in mind for impact.

The Complete Gemstone Hardness Chart

Stones are listed from softest to hardest, with a quick note on durability and care. Many natural stones vary slightly, so ranges are given where appropriate.

StoneMohs hardnessDurability & care notes
Selenite2Very soft; dissolves in water; display/handling only
Amber2–2.5Soft, organic; scratches easily; avoid chemicals
Lepidolite2.5–4Soft; keep away from water and knocks
Pearl2.5–4.5Organic; soft; avoid chemicals, perfume, water
Calcite (incl. orange/blue)3Soft; reacts to acids; no water cleansing
Coral3–4Organic; soft; protect from chemicals
Howlite3.5Soft and porous; often dyed; handle gently
Azurite3.5–4Soft, sensitive; no water
Malachite3.5–4Soft; toxic dust if cut; never put in water
Rhodochrosite3.5–4Soft; protect from scratches and acids
Fluorite4Soft for jewelry; fades in sun; cleaves easily
Larimar4.5–5Moderate; protect from knocks
Lapis lazuli5–5.5Moderate; porous; avoid water and chemicals
Apatite5Moderate; brittle; protective settings only
Obsidian5–5.5Glass; can chip; moderate scratch resistance
Hematite5–6Moderate; can chip; keep dry to avoid rust
Turquoise5–6Porous; avoid water, oils, chemicals
Moldavite5.5–6Natural glass; handle with care
Opal5.5–6.5Contains water; can crack if too dry; gentle care
Sodalite5.5–6Moderate; protect from scratches
Moonstone6–6.5Can cleave; protective settings for rings
Labradorite6–6.5Moderate; avoid hard knocks
Amazonite6–6.5Moderate; can cleave; gentle handling
Sunstone6–6.5Moderate; everyday wear with some care
Pyrite6–6.5Keep dry; can tarnish/rust
Nephrite jade6–6.5Lower hardness but very tough
Tanzanite6–7Brittle; not ideal for daily rings
Jadeite jade6.5–7Tough and durable; good for jewelry
Peridot6.5–7Moderate; avoid hard knocks
Kunzite6.5–7Fades in sun; cleaves; gentle wear
Zircon6.5–7.5Good but edges can abrade
Garnet6.5–7.5Durable; good everyday stone
Quartz family (amethyst, citrine, rose & clear quartz, smoky quartz)7Durable; great for everyday jewelry
Agate, jasper, carnelian, onyx, aventurine, tiger’s eye7Durable chalcedony/quartz; everyday-friendly
Iolite7–7.5Durable but can cleave
Tourmaline7–7.5Good durability for most jewelry
Aquamarine7.5–8Hard and durable; excellent for rings
Emerald7.5–8Hard but often included/brittle; some care
Morganite7.5–8Hard and durable; great for jewelry
Spinel8Very durable; underrated ring stone
Topaz8Hard but cleaves; settings should protect it
Cubic zirconia8–8.5Durable lab stone
Alexandrite / chrysoberyl8.5Excellent durability
Ruby (corundum)9Extremely durable; ideal for daily wear
Sapphire (corundum)9Extremely durable; ideal for daily wear
Moissanite9.25–9.5Near-diamond durability
Diamond10Hardest natural material; can still chip on impact

popular gemstones sorted by Mohs hardness

How to Use This Chart

Choosing a stone for a ring. Rings take the most abuse, so favor stones at 7 and above — quartz, garnet, tourmaline, beryls (aquamarine, morganite), spinel, sapphire. Softer or cleavage-prone stones (opal, moonstone, tanzanite, emerald) can absolutely be worn, but choose protective settings and treat them gently. Earrings, pendants, and brooches see far less wear, so softer stones are much safer there.

Storing your collection. Harder stones scratch softer ones, so don’t toss everything in one pouch. Wrap softer pieces separately, and never let a diamond or sapphire rattle against an opal or pearl.

Cleaning safely. Hardness and water-sensitivity together decide how you clean a stone. Many soft stones are also porous or water-soluble — selenite, malachite, turquoise, pyrite — and should never go near water. For the full method-by-method breakdown, see how to cleanse crystals, and for the water question specifically, which crystals can and can’t go in water.

Frequently Asked Questions

What is the hardest gemstone?

Diamond, at 10 on the Mohs scale — the hardest natural material known. Among more affordable stones, moissanite (9.25–9.5) and the corundum gems sapphire and ruby (both 9) are extremely hard and excellent for everyday wear.

What hardness is good for everyday jewelry?

A hardness of 7 or higher is the general benchmark, because everyday dust contains quartz (7) and can scratch anything softer over time. Stones below 7 can still be worn — especially in earrings or pendants — but rings benefit from harder, tougher stones and protective settings.

Is a harder gemstone always more durable?

Not necessarily. Hardness measures scratch resistance, not resistance to chipping or breaking. Diamond is the hardest stone yet can chip on impact, while jade is much softer but very tough. Consider both properties for jewelry you’ll wear hard.

Can soft stones be worn as jewelry?

Yes, with care. Soft stones like opal, turquoise, and moonstone make beautiful jewelry but do best in protective settings, in pieces that take less impact, and with gentle cleaning. Save them from daily rough wear and they’ll last for years.

Where to Go From Here

Hardness is the quiet fundamental behind every smart buying and care decision you’ll make. Keep this chart handy: check a stone’s number before you set it in a ring, store it, or clean it, and you’ll avoid the most common ways collections get damaged.

From here, learn to care for your stones safely with how to cleanse crystals and how to charge crystals, double-check sensitive stones against which crystals can and can’t go in water, and if you’re choosing a stone to wear, see how to buy gemstones online without getting scammed. New to all of this? Start with our beginner’s guide to healing crystals.

What’s the softest stone in your collection — and how do you keep it safe? Tell me in the comments.

This guide is for informational and educational purposes. Hardness values are typical ranges; natural stones vary, and treated or composite materials may differ.

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