Opal meaning & facts
Opal is a birthstone for October. Opal is linked with creativity, hope, imagination and inspiration.
- Birth month
- October
- Colour
- Shifting rainbow colours
- Mineral
- Hydrated silica
- Hardness (Mohs)
- 5.5–6.5
- Main sources
- Australia (most of the world's supply), Ethiopia and Mexico
Opal facts
- Opal's "play of colour" comes from tiny silica spheres that split light into rainbow colours.
- Opal contains water, typically a few percent of its weight.
- Australia produces the large majority of the world's precious opal.
October also has another birthstone: Tourmaline.
Birthstones by month
Frequently asked questions
What does opal mean?
Opal is linked with creativity, hope, imagination and inspiration.
What month is opal the birthstone for?
Opal is a birthstone for October. The other October birthstone is Tourmaline.
How hard is opal?
Opal rates 5.5–6.5 on the Mohs hardness scale, which runs from 1 (talc) to 10 (diamond).
Gemstone meanings are traditional beliefs, shared for interest rather than as proven properties.