(via agade list)
http://www.biblicalarchaeology.org/reviews/the-coins-of-herod-a-modern-analysis-and-die-classification/
Herod's 'disappointing numismatic record' and concentration on smaller denominations are reflected in the reign of another Herod, as attested in Matthew 22.15-22 ("'Whose likeness and inscription is [on this coin]?' They said: 'Caesar's'. Then he said to them: 'Render unto Caesar the things that are Caesar's ...'").
It should be noted that Herod was continuing a tradition established by the Hasmoneans, as mentioned in this Wikipedia article: http://en.wikipedia.org/wiki/Hasmonean_coinage (http://en.wikipedia.org/wiki/Hasmonean_coinage)
"Only bronze coins in various denominations have been found ..."
Patrick