What is Opal?

Opal, a stone in the Silica group, is a hardened silica gel and is composed of tiny layers of silica. When the layers are of similar size, light diffracts into the colours of the rainbow and so the opal looks like a flash of coloured light. – this is indicative of precious opal. Precious Opal comes in different colours including:

•    Black opal
•    Fire opal
•    White opal

These are the backgrounds for the iridescent colours which are typical of the opal. It is the most highly prized of the silica gemstones.

‘Common’ Opal is usually opaque.

It is found in the cavities of sedimentary rocks and in the veins of igneous rocks.

Opal is found in Australia, Brazil, USA and Mexico.


The oldest recorded Opals are those found by the anthropologist Louis Leakey in 4000 B.C in a cave in Kenya.

Ancient Romans wore Opals which had been sourced from Hungarian mines.

Australia has been producing Opal in large quantities since the nineteenth century.

Queen Victoria favoured Opals.


In ancient times, it was thought to be essential to carry an opal as this afforded protection against being poisoned by ones enemies which was a prevalent practice.

In Roman times, the Opal was thought to bring good luck as the rainbow effect of the colours was considered to be a symbol of hope and it also was supposed to be able to make the wearer invisible from their enemies.

The Opal was considered in medieval Europe to have the ability to preserve blond hair and that good memory could be preserved by touching the forehead with an Opal.

Opal, it is said is the stone signifying emotional, physical and mental harmony and is supposed to encourage passion.

It is the birthstone for October and as such, signifies purity, hope and health. “Octobers child in darkness oft may grope, the Iridescent Opal bids it Hope.” (Source unknown)


Caring for Opal

Opal is comparatively soft and therefore more fragile than many other gems. It can crack if it dries out or is moved from warmth to cold.

Opal should be kept in a soft, padded bag or pouch and cleaned with a soft dry cloth or with a damp cloth. They can be washed in warm soapy water. They should not be cleaned with chemicals and ultrasonic treatments and steamers should be avoided.

Caring for Opal (Summary)

•    Keep in constant temperature to prevent cracking
•    Keep in soft padded pouch
•    Wash in warm soapy water and clean with dry or damp cloth
•    Do not use chemicals or steamers.