LESBOS. Mytilene. Circa 521-478 BC. Hekte (Electrum, 10 mm, 2.53 g, 4 h). Gorgoneion facing, surrounded by snakes and with a protruding tongue. Rev. Bearded head of Herakles to right, wearing lion's skin headdress; neck truncation formed by two rows of small squares, four above and six below; behind head, rectangle with irregular field; all incuse. BMC 14. Bodenstedt 19.1 (c/γ). SNG von Aulock 1691. Beautifully struck and with a powerful gorgoneion. Extremely fine.
This is an exceptional example of a series of issues from Mytilene that is characterized by having a complete type in incuse on the reverse, rather than the traditional incuse square. However, to remind the user of that original style of incuse reverse, utilized by all the early minters of electrum, a tiny square appears on the reverse behind the main type.