Apotropaic magic is a ritual observance that is intended to turn away evil. In accordance with the magical law, "Like Affects Like,", eyes were and still are used to ward off the "evil eye".
Isle of Lesbos is rare enough; the amuletic "Mystic Eye" on this coin is absolutely unfindable!
The incuse square on the reverse is intended to function as a miniature altar or temple.
Billon 1/48th stater, BMC Lesbos, pp. 152 - 3, 26 ff., aVF, weight 0.271g, maximum diameter 5.9mm, obverse two apotropaic eyes; reverse incuse square. RARE +++