A Question About Word 'Pfennig' ... And Middle Ages Coin Making

In German you've got pfennig, in Dutch penning, in English penny, and they probably all have the same origin. What that origin is, is up to debate. From the wikipedia page for penny: "The etymology of the term "penny" is uncertain, although cognates are common across almost all Germanic languages[n 3] and suggest a base *pan-, *pann-, or *pand- with the individualizing suffix -ing. Common suggestions include that it was originally *panding as a West Germanic form of Old High German pfant ("pawn" the sense of a pledge or debt, as in a pawn shop putting up collateral as a pledge for repayment of loans); *panning as a form of the West Germanic word for "frypan", presumably owing to its shape; and *ponding as a very early borrowing of Latin pondus ("pound"). Recently, it has been proposed that it may represent an early borrowing of Punic pn (Pane or Pene, "Face"), as the face of Carthaginian fertility goddess Tanit was represented on nearly all Carthaginian currency"

As for the pan: there are coins that are only embossed on one side, those coins in Dutch are called brakteaat. A google images search returns this:https://www.google.nl/search?q=brak...050&bih=1575, to give you an idea of what those coins looked like.

I had always thought that a penny was a unit of weight before it was used to refer to a coin made to that standard. Maybe I have things backwards in my head.

I am also confused how it is always said that the penny was modeled on the denarius and drachma--the older silver coins were not only heavier, but also constituted "real" money in their day--enough to buy a good helping of food.