James W. Marshall, a sawmill operator, discovers gold (lawful Money) in the American River, at Sutter’s Mill, in Coloma, California, starting the California Gold Rush.

       Postscript: In following decade, California produced more gold than the rest of the world had produced during the previous century and a half.  But there were no federal mints to press out coins.  Nor were there enough foreign coins in California to satisfy public demand.  As a consequence, private mints filled the void.

       [updated 1/29/2022] Thanks to Jim Lorenz for his contributions to this entry.