Re: ghost crystal problem

[Glenn Knapp <kahuna@VCN.COM>]

At 01:37 PM 01/30/2001 -0800, you wrote:
> >In preparation for a demonstration about the index of refraction, I
> >placed several "ghost crystals" in distilled water as per the directions
> >included with the crystals.  They have expanded greatly in size and are
> >clear, just as expected.
> >
> >The problem is that there are tiny air bubbles trapped in the crystals,
> >so they are not completely invisible.
> >
> >Has anyone else had this problem in preparing them? Any insight will be
> >greatly appreciated.
>
> I have never heard of these, but it would seem prudent to deair the
> water by boiling before using it if you are having this problem.
>
> Leigh

Make the ghost crystals several days in advance.  Use distilled
water.  Once you've put the crystals into the water, put the whole thing in
the refrigerator.  This usually eliminates the bubbles.

Glenn