COINS OF THE GREEK WORLD
PTOLEMAIC KINGDOM
Ptolemy I Soter, 323-284. Tetradrachm 305/284, Alexandria. Diademed head of Ptolemy I to r. Rev. BAΣIΛEΩΣ ΠTOΛEMAIOY Eagle standing to l. on thunderbolt; P over monogram on l. 14.22 g. SNG Cop. 70. Svoronos 255. About extremely fine-good very fine.
It would seem that the die cutter corrected a mistake in the r. reverse field, perhaps inadvertently placing the control marks there instead of on the left side.