Hi John,
Your led lamp with an output of 395nm is perfect for detecting the 
fluorescence of seashells. The red fluorescence visible in some shells 
such as the mappas is due to the presence of porphyrins in the outermost 
layer of shell material. The porphyrins have a maximum absorption of UV 
at around 400nm, the reason your light works well. Other pigments may 
contribute some fluorescence, but nothing like the porphyrins. Also, the 
actual mineral composition of the shells can produce fluorescence. A UV 
light source with a filtered output to reduce the blue and purple color 
is best in order to more accurately observe the fluorescence.
http://www.rbridges.com/autofluorescencePlate.jpg
Cheers,
Randy Bridges

----------------------------------------------------------------------
[log in to unmask] - a forum for informal discussions on molluscs
To leave this list, click on the following web link:
http://listserv.uga.edu/scripts/wa-UGA.exe?SUBED1=conch-l-L&A=1
Type your email address and name in the appropriate box and
click leave the list.
----------------------------------------------------------------------