Who else buys the most common type coins and why?

[shirohniichan]

Usually I look for the scarcest type coins I can find that don't command much of a price premium when building a collection. I use this method for my US type set, for example.

 

Recently I found myself looking for the most common as I searched for an example of an 18th century Spanish pistareen. The 1721 is the most commonly dug 2 reales coin in the Mid-Atlantic states, so I thought it best to represent pistareens that circulated widely in the American colonies. I can see this approach when building a collection of trade coins (e.g. shekels of Tyre or Maria Theresa talers) as they are the rule instead of the exception.