Interestingly, these endearing marine creatures are often found depicted in mythological Greek tales where Poseidon, the sea god is said to drive a chariot pulled by sea horses. They are also called ‘Hippocamp’ and often decorated mosaics and Roman baths and can be seen on the 18th century Trevi fountain in Rome.
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Another mythology inspired bit of jewelry is the Pandora bracelet. This, however, has little more to do with mythology than the name, but deep on their website, you can find a reference to the curiosity of Pandora being the inspiration for this line. Well, I found it once on a web site. I can't find it on their current web site. My wife has one of these bracelets. It is essentially a charm bracelet, but instead of the charms hanging, they slide around the bracelet. It is pretty neat looking.