They are considered the oldest mass-produced type of coin in the world. They have been used for trade since the days of the Greeks. By 612 BC, the Persians were using silver coins as money. As a result, certain ancient and old silver coins have become highly collectible, such as the Miliarense. People also collect silver coins today, such as the more modern Morgan Dollar (although few such items have much value beyond their actual silver content).

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