The sport of Auto Racing.
Soccer
Nobody MADE opals. They're mined out of the ground.
It represents rugby.
swinning
Tennis
Opals cannot be used as foods. They are hard, precious stones.
Neither opals or any other gemstone will make you invisible.
Some opals are known as black opals, this is when they have a mainly black colour. In general a black opal is very dark blue and has flecks of other colours within
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No. When opals were first found in Australia, they were not thought to be opals because they were a milky white in appearance. Opals found elsewhere in the world were mostly black.
Opals are amorphous because they lack a crystalline structure. Their formation involves the precipitation of silica spheres in a disordered arrangement, which gives opals their unique play-of-color appearance. This lack of a crystal lattice is what differentiates them from most other gemstones.