I bought a bag of little snail shells. The underside of the shell have a really pretty pattern. They were in the flower arranging section of the craft store but I thought they'd look good cast in resin jewellery.
All these items are listed in my Etsy shop.
I haven't added links to the individual items but if you visit my Etsy shop and put "snail" or "shells" in the search box you'll find everything listed. Click here to visit my Etsy shop