Greek is the Word

No, this little pin does not read "eat" (though it would make an excellent gift for a chef). The letters are sigma delta tau, and it is a vintage pin from that sorority, made with (claims the vendor) authentic seed pearls, a little diamond, and 10 karat gold. My favorite element has to be the Doric column stem--this and its like often showed inspired decorative design.

For readers outside United States: fraternity and sorority pins such as this one were once a staple of American university life; even the fraternal versions are often embellished with gemstones and enamel, because in the 1950s and 60s a girl was "pinned" with her boyfriend's frat emblem, as a sort of pre-engagement notice that the lady was under claim.

I think they're just lovely purely as a flash of color and sparkle to wear on a lapel or collar. They can be found in their hundreds on the usual online sources like eBay and Etsy.