Sagacia’s Statement Ammolite Earring Ammolite Earring is an iridescent gemstone that was first discovered in Canada. It is a multi-colored gemstone that appears like an opal and is formed out of a fossilized shell of ammonite, which is an extinct mollusk. In the world of the gemstone jewelry industry, ammolite is a trade name that is used for gem-quality material obtained from fossilized ammonite shells. The rarest of rare gem-quality ammonite specimens are called ammolite.