Hard & Soft Stones
By Hard Stones, we mean the likes of emerald, sapphire, agate, hard quartz and stones in the Corundum family; essentially, any stone above 7.5 on the Mohs scale.
By Soft Stones, we usually mean equal to or lower in hardness than turquoise, rhodochrosite, opal, apatite, fluorite, etc. I.E. stones with a Mohs scale rating below 7.5.
Keep in mind that there exist far too many stones to list here and you can likely come across some stones with varying degrees of hardness within the same stone piece.
Want to learn more?
> Here is a good resource on the Mohs hardness scale <
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