Bill, it's not damascus, it's high carbon steel, clay coated during the heat treat to differentially harden it, then etched to show the temper line :D
My neck knife has a 3" blade and is about 7" OAL, so the one you posted a pic of would definitely work for a neck knife (real nice knife btw) The lower knife in my first pic is based on Doug Campbell's popular caper knife, and is 6-3/4" OAL, or there-abouts. I've made 3 or 4 in that style and find them really handy. I cleaned and butchered two deer with one last year to prove to a guy you don't need a 5" blade to clean a deer
I didn't think I'd like a neck knife until I tried one. Now I wear mine most of the time when I'm not at work.