Oldies but Goodies - Fossils

I live about 11 miles from Holzmaden, a little town which is known for the fossils that are found in the ground in and around the city. There's the Urweltmuseum (Ancient World Museum) with fascinating specimens, some of them very large, beautifully displayed. If you are an amateur fossil hunter, there are two quarries where you are can do some digging yourself. I remember a very hot summer day that we spent at one of the quarries with a guest from India, but at least she found some little shells to take home - although I had hoped for an ammonite myself.

Our latest Jewelry Artisans Community Oldies but Goodies Challenge was about fossils and to be honest I was a little surprised there was so little participation. Coming from a region where fossils are still found, I may be more fascinated by them than others, but in jewelry making fossils are by no means unusual.
Have a look.

1, 4, and 5 Cat's Wire
2 Violetmoon's Corner
3 and 6 MC Stoneworks

If you are interested now what kind of fossils these are, keep reading and don't forget to click the links for more information.

1 and 6 are fossil corals. 
Actually it's the ancient corals' skeletons that are fossilized and preserved in these agatized stones.
They are appreciated for their often flower like patterns.

2, 3, and 5 are ammonites. Ammonites were marine molluscs that went extinct millions of years ago. The living relatives of these cephalopods are for example octopus, squid, cuttlefish, and nautilus.
Ammonites with their pretty spirals are used a lot in jewelry.

4 is orthoceras, also a cephalopod, but straight shelled.