rust-like patches on shells

[marlo]

There is a condition commonly referred to as Byne's Disease that can affect shells stored in certain conditions encoraged by damp.  However, it is not really a disease nor caused by bacteria.  See <a href="http://z14.invisionfree.com/Conchologist_Forum/index.php?showtopic=216" target="_blank"><!-- m --><a class="postlink" href="http://z14.invisionfree.com/Conchologist_Forum/index.php?showtopic=216">http://z14.invisionfree.com/Conchologis ... wtopic=216</a><!-- m --></a> for a discussion.

A rust-like discoloration is not entirely uncommon and can occur as a result of material the animal incorporates into the shell.  It would be helpful if you can ascertain whether the discoloration is part of the shell (in the enamel) or a deposit on it and if it may have occurred during storage.  If it occurred during storage through some mechanism, then it probably will at least partially rub off (assuming the shells were reasonably cleaned when placed in the collection).  This test will help determine the cause.  Photos would be a big help too.  <span class="petit">--Last edited by marlo on 2010-03-29 21:23:47 --</span>