The Hardest Thing in Your House Isn’t What You Think!

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Hardness isn’t about how strong or durable something is—it’s about how resistant it is to being scratched. Scientists measure this using the Mohs scale, a ranking from 1 to 10 that compares materials based on how easily they can be scratched by something else.

The Mohs scale was created in 1812 by a German scientist named Friedrich Mohs. At the top of the scale, ranked 10, is diamond, the hardest naturally occurring material. At the bottom, ranked 1, is talc, which is so soft it can be crumbled in your hands.

So where does sandpaper fit in? The rough grit in sandpaper is made of corundum (Al2O3), which has a hardness of 9 on the Mohs scale—just one step below diamond! That means it can scratch almost anything in your home.

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Corundum is an extremely tough mineral found in nature, but it’s also the same material used in rubies and sapphires. That’s right—the same substance that makes beautiful gemstones is also what makes sandpaper so effective.

The test is simple: take two materials and rub them against each other. If one leaves a scratch on the other, it means it’s harder. If both scratch each other, they have the same hardness level.

Hardness isn’t the same as strength. In contrast, steel isn’t as hard as corundum, but it’s much stronger and more durable. Next time you see sandpaper, remember—it’s harder than almost anything else in your house. And unless you own diamond jewelry, it’s probably the hardest thing you own.

The more you know!

Stay tuned,

BREEFX ✨

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