best opal stone ever found -- a 6.0-centimetre (2.4 inch) multi-coloured gem unearthed in the Outback named the Virgin Rainbow.

The South Australian Museum said the stone, valued
at more than Aus$1.0 million (US$730,000). "It's of
unequalled quality, it's a fully crystal opal. "It's almost
as if there's a fire in there; you see all different colours.
As the light changes, the opal itself changes. It's quite
an amazing trick of nature."