It’s absolutely exquisite. NATURAL BLACK COLUS FOSSIL with Ammonite. It’s from the sea. it’s exquisite it’s encased. very beautifully in Sterling. List price when bought was $22. and the chain itself is positively gorgeous and very high-quality. iIt’s beautiful. The chain is beautiful. It’s gorgeous. It’s substantial it’s huge.there is a makers mark but after researching this I can’t seem to find any information. I have several of this mark since many of my items are inherieted I’m not the original buyer so I have limited knowledge. My very well educated opinion is this was made by an artist in my area and many were. purchased as a collection by this same artist. The mark is identical on several pieces from MOMS collections whatever the case may be he / she was an excellent jewelry designer and this mark TLC likely means it was made with “TENDER LOVING CARE “ One of my experts in GEMOLOGY thinks it could be a NAVAJO mark but I honestly can’t confirm that selling as described.