Red Carnelian Tumbled Stone

Carnelian is chalcedony - microcrystalline quartz, SiO₂, Mohs 7 - coloured by fine iron oxide to a warm orange-red. It is translucent where banded agate is opaque, glowing when light passes through it.

The colour runs from pale apricot to deep brownish-red, often within a single strand. Iron is the whole of it: the same element that rusts orange, dissolved through the silica.

Held to the light it glows; against the hand it reads as solid colour. That translucency is what sets carnelian apart from the opaque red jasper it is kin to, and from the banded agates - the same family, a different way with light.

Asked often

Why does it glow when held up?
Carnelian is translucent - light passes through the microcrystalline quartz and returns warmed by the iron within, so the bead seems lit from inside. The opaque red jasper it is kin to does not do this.

How is it different from agate or onyx?
All are chalcedony. Carnelian is the translucent orange-red; agate is banded; onyx is the straight-banded black. Same mineral, different colour and pattern.

Why did Rome use it for seals?
Hot sealing wax does not stick to carnelian, so a carved carnelian signet pressed a clean image every time. It was the favoured seal-stone of the ancient world.

How do I look after them?
Wipe with a soft cloth. Hard-wearing at Mohs 7; rest them out of prolonged strong sun, which can pale the red.

1. Carried in a pocket or a bag, or held in the hand.
2. Kept in a small dish, on a desk, or on a shelf - each stone is a little different.
3. Wipe with a soft cloth; rest them out of strong sun, which can pale the red over time.

Each stone is tumble-polished and unique, so a set varies a little stone to stone. Many keep a stone where they will see it each day, or carry one in a pocket; that is a matter of preference.

Pocket stones to keep and carry. Wipe with a soft cloth and rest them out of prolonged strong sun, which can pale the colour. Hard-wearing at Mohs 7.

• Stone: Red Carnelian · orange-red chalcedony
• Hardness: Mohs 7
• Character: Apricot to deep brownish-red · translucent
• Lustre: Vitreous · translucent
• Form: Tumbled stones · polished, each unique · sold in a set
• Origin: India
• Care: Wipe with a soft cloth · rest out of strong sun

Carnelian is among the most worked stones of the ancient world. The peoples of the Indus Valley etched it with patterns in white thousands of years ago; Egypt set it into the gold of pectorals and amulets; and Rome made it the favoured signet stone, carved in reverse to seal letters and documents.

For its warm colour carnelian was carried as a stone of courage and steady drive across many cultures - named here as what people believed. The glow is iron and light; what it is taken to quicken is the wearer’s.