What are some examples of obsolete letters from the Greek alphabet

6th letter in the Coptic alphabet - Community

What would the Greek letters Θ Ξ Φ Ψ look like if they had been adopted by the Romans and were part of the Latin alphabet? Also what would San (Ϻ

A comparative vocabulary of the Greek and Gaelic languages : Stratton, Thomas, 1816-1886 : Free Download, Borrow, and Streaming : Internet Archive

Greek alphabet

How would you spell all the names of the Greek letters with Greek letters themselves? (example: α would probably be something like 'αλφα' in the Greek spelling) - Quora

How many times has the Greek alphabet been changed? - Quora

Greek Numbers

Kata Biblon Archaic Letters

How would you spell all the names of the Greek letters with Greek letters themselves? (example: α would probably be something like 'αλφα' in the Greek spelling) - Quora

What ancient Greek letters are still used today? - Quora

How to write a sentence only using each of the Greek alphabet once? What does it say in English - Quora