U+03E0 "Ϡ" Greek Letter Sampi Unicode Character

U+03E0 "Ϡ" Greek Letter Sampi is an archaic Greek letter that was used in the ancient Greek numeral system to represent the number 900, originally derived from the Phoenician letter tsade. Its shape has varied over time; in some ancient inscriptions it appears as a vertical stroke with a horizontal bar or a form similar to a modern pi, and it was later used in medieval Greek manuscripts as a numerical symbol. The sampi eventually fell out of use as a standard alphabetic letter by the classical period but persisted as a numeric sign, and it was revived in some early modern typographic traditions before being encoded in Unicode for historical and technical purposes.