Hello, I wrote an answer here that looked at the monetisation the Early Medieval English economy, and the role that coinage played in contemporary exchange. There's an answer linked in that answer which contains some more information about the design and manufacture of the 9th-11th Century penny, its ubiquity and ease of use.

I also wrote an answer here which looked at 14th Century currency as viewed through the lens of A Knight's Tale in which I briefly touch on the popularity of the Edward III 4d 'Groat' coinage, as well as the 'Noble', the first 'common' use English gold coin, or at least the first English gold coin to see successful use in commerce.

A tl;dr of those posts is that the Medieval economy, at least in England, was relatively extensively monetised, with the silver penny as its mainstay. While earlier gold coinage did exist, it was largely ceremonial, and gold coins didn't really enter economic use until the 14th Century.

'English' silver usually came from North Wales, although the discovery of large silver deposits on the site of what would become Carlisle in the 1090s lead to a boom of English silver production and the rapid growth of Carlisle as a major boom town.