A good overview of early U.S. coinage?

[Jerry Robinette]

I've been collecting ancients and some world material for a few years
now, but am just starting to get interested in the early U.S. coinage
and currency. Can anybody recommend a good overview? I'm hoping to find
a book or website that provides a surface-level introduction to the
entire period, with pointers to other resources for more detail.
(Something analagous to Wayne Sales' books on collecting ancients would
be perfect, I think.)

I'm aware of the recently-released Whitman Encyclopaedia, but from what
I've read that's more of a price guide/catalogue rather than an actual
survey of the field. The Colonial Coin Collectors CLub has only a
couple of paragraphs by way of intro on its website. And I have access
to a copy of Breen's encyclopaedia.

Any thoughts would be greatly appreciated!

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