A stone's true properties are physical and measurable: chemical composition, crystal system, hardness, density and the origin of its colour. Knowing them helps you choose durable jewellery and spot imitations — far more reliably than "virtues". Here are the essentials, jargon-free.
Not every "stone" is a mineral. Quartz is a mineral (silicon dioxide); lapis lazuli is a rock (several minerals); obsidian is a volcanic glass, not crystalline. This nature explains their behaviour (hardness, cleavage, sensitivity).
Hardness measures scratch resistance, from 1 (talc) to 10 (diamond). It's the key criterion for use: above 6.5-7 the stone takes daily wear; below, it scratches quickly. Find each stone's hardness in our summary table.
Colour comes from trace metals (iron turns quartz purple or yellow, copper turns malachite green), from inclusions (aventurine, tiger's eye) or an optical effect (labradorite's flashes, moonstone's veil). Heating or dyeing can alter it — hence the importance of seller transparency.
Many stones are treated: heating (aquamarine, citrine), dyeing (agate, howlite), resin stabilisation (turquoise). These are legitimate if disclosed. A too-vivid, uniform colour on a cheap stone should alert you. See our natural stone jewellery guide.
To distinguish from physical properties: the energy or therapeutic properties attributed to stones are traditions and are not scientifically demonstrated (see sources). They replace no medical advice.
Its measurable physical properties: chemical composition, nature (mineral, rock or glass), crystal system, hardness on the Mohs scale, density and the origin of its colour. These determine a piece's durability and use.
From trace metals (iron, copper, chromium), mineral inclusions, or an optical effect (flashes, veil). Heating or dyeing can alter it: a serious seller says so.
Unlike physical properties, which are measurable, the energy or therapeutic properties attributed to stones are traditions and are not scientifically demonstrated. They replace no medical advice.
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