Romanization of Greek Greek numerals which employed the entire alphabet, including the nonstandard letters digamma, stigma, or sigma-tau (placed between epsilon and zeta), koppa (placed between pi and rho), and sampi (placed after omega). As revised in 2001, ELOT 743 provides for the uncommon characters to be given (in Greek) as $ for stigma, + for koppa, and / for sampi. These symbols are not given lower-case equivalents. When used as numbers, the letters are used in combination with the upper "keraia" numeral sign ⟨ʹ⟩ to denote numbers from 1 to 900 and in combination with the lower "keraia" ⟨͵⟩ to denote multiples
Koppa (letter) Koppa (letter) Koppa or qoppa (; as a modern numeral sign: ) is a letter that was used in early forms of the Greek alphabet, derived from Phoenician qoph . It was originally used to denote the /k/ sound, but dropped out of use as an alphabetic character in favor of Kappa (Κ). It has remained in use as a numeral symbol (90) in the system of Greek numerals, although with a modified shape. Koppa is the source of Latin Q, as well as the Cyrillic numeral sign of the same name (Koppa). In Phoenician, qoph was pronounced ; in