4.38 x 2.5 x 0.5 in. (11.1 x 6.4 x 1.3 cm.) ...

The 'Virgin Rainbow' is one of the world's rarest and most expensive opals. This extremely rare opal exhibits incredible fluorescence with a rainbow of different colors that make opal so distinctly ...

12 x 18 x 18 cm. (4.7 x 7.1 x 7.1 in.) ...

An opal so fine it has been valued at over $1 million is about to go on public display for the first time. Michelle Starr is CNET's science editor, and she hopes to get you as enthralled with the ...