> Subject: Re: What kind of Blacklight(s) work best??
> Date: Mon, 23 Aug 1999 18:39:15 -0600
> From: NORA BRYAN <[log in to unmask]>

> On blacklights
> I believe we are talking about ultraviolet lamps.  Many mineral
> collectors have displays of fluorescing minerals, and they use
> ultraviolet lamps.  There are actually two lamps, a short-wave UV lamp
> and a long wave UV lamp.  Many minerals fluoresce under long-wave UV,
> and fewer fluoresce under short wave.  A mineral may fluoresce different
> colours under the different lights.

Actually many more minerals fluoresce under short-wave UV than under
long-wave. Many minerals and other fluorescent substances, probably
including shells, that fluoresce under both SW and LW often show
brighter fluorescence with SW.  Some UV lamps are available that can
emit LW at one end and SW at the other.  You definitely do want the
fluorescent tube type rather than the incandescent bulb.

--
Cecil N. Bankston
Baton Rouge, LA USA