An opalescent puzzle.

[Topher Cooper DTN-225-5819]

The following was part of a posting in a local bulletin board.

I frequntly wear opals, and have some that are brilliantly coloured
and beautiful. [My grandmother] told me she could not wear opals, and
proved it. She took my blue Australian opal triplet (opal covered in
[quartz] crystal and backed with black onyx - protects a soft stone and
deepens the colour) and held it in her hand. It turned milky white and
lost all colour. I took it back and the colour returned.

Does anyone have any explanations for this phenomenon?

People may post their responses, or mail them to me. I will summarize any
of the latter.

Topher Cooper

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[je...@rtech.uucp]

>
> [My grandmother] told me she could not wear opals, and
> proved it. She took my blue Australian opal triplet (opal covered in
> [quartz] crystal and backed with black onyx - protects a soft stone and
> deepens the colour) and held it in her hand. It turned milky white and
> lost all colour. I took it back and the colour returned.
>
> Does anyone have any explanations for this phenomenon?
>

> Topher Cooper

Opals will absorb moisture from the skin. When this happens, then turn milky.
When the moisture evaporates, they turn back to their original colors.
--
Jeff Lichtman at rtech (Relational Technology, Inc.)
"Saints should always be judged guilty until they are proved innocent..."

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