Attached are the US Banking Line Pair

The Indianhead Cent 13-cent stamp

A medieval coin of Monaco on a Monaco stamp

The US Postal Service celebration of Numismatics.

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And here are two Greek stamps celebrating ancient (Roman imperial i.e., Greek colonial) coins celebrating coins that honor Pythagoras. 

Below them, the famous Rhodes stater with the head of Helios, accepted as the head of the Colossus of Rhodes.  The flower is said to be a "rose" and hence a pun on the name but the island is known better for the hibiscus, which, in fact, this more closely depicts.

And a shekel of the First Revolt.

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A bit obscure... a Swedish coin on a USPS stamp honoring the Treaty with Sweden.

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