Yes, the Ptolemaic dynasty was started by Ptolemy, one of Alexander's generals. He wrote an account of Alexander's conquests which does not survive but which was used by Arrian, whose history of Alexander the Great does survive. Arrian thought Ptolemy's version was reliable because it would be unseemly for a king to lie.
There's a very nice archaeological museum in Thessalonica which would probably be delighted to get the coin, but no chance of that happening.
“There’s a very nice archaeological museum in Thessalonica”
Sigh. Well, maybe next year...