The Dyo ring is designed after the Ionic order forms, one of the three classical orders of classical architecture. 

 

The Ionic order originated in the mid-6th century BC in Ionia, the southwestern coastland and islands of Asia Minor settled by Ionian Greeks, where an Ionian dialect was spoken. The Ionic order column was being practiced in mainland Greece in the 5th century BC. It was most popular in the Archaic Period (750–480 BC) in Ionia. The first of the great Ionic temples was the Temple of Hera on Samos. 

 

The Parthenon, although it conforms mainly to the Doric order, also has some Ionic elements. A more purely Ionic mode to be seen on the Athenian Acropolis is exemplified in the Erechtheum.