Yes, I thought that as one of the possibilities although the preservation of my past find of lobster antena were not preserved as pyrite but within a phosphatic nodule such as the below specimen(the below image is from http://www.dmap.co.uk/fossils/).
Linuparus scyllariformis (Bell)
Photo's on dmap are copyrighted and need permission for use, from Alan Morton. I have edited your post to link to the specimen. Edited by Bill G 2015-01-21 19:49:56