Can Opal Absorb Water ?

by William
(Yuma, AZ.)

Welo Opal

Welo Opal


I was working with a piece of Crystal Opal.

It showed nice blue flash when I backed it with black. Using wet or dry I prepared it to epoxy it to the back.

I left it on the counter for about an hour and it dried out.

When it was dry it became milky white with the blue flash intact. I proceeded to clean it and finish my wet sanding and it returned to water clear.

Is that normal? Why did it happen?


Hi William,
Thank you for your question on this one.

Actually, the answer for this is fairly straight forward I would say. It sounds to me that you are working with Ethiopian Welo opal from Africa.

Though quite beautiful, Ethiopian welo crystal is a hydrophane opal, this type of opal absorbs water and while working it or if it just gets wet, it brings about colour changes to the base colour tone of the opal.
High rainfall conditions and even strong humid conditions may also have the same effect on the opal.

However, it is not a permanent condition for as the opal dries out, it will return to normal over a few days with the opal colours returning to normal as well.

Fortunately our Australian crystal opal is NOT of the hydrophane type and can be cut and worked normally with no side effects whatsoever.

Hope this clarifies things a little for you and thank you again for your very valid question.

          Kind regards,


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