1860 G$20 Clark, Gruber & Co. K-4

Coin / United States of America / G$20 / Clark / 1860 / Denver, Colorado

The Clark Gruber “Mountain $20,” has been considered a key to the pioneer gold series since the early 20th century. Today, there are only 15 examples encapsulated at either of the third- party grading services, and a trio of genuine, ungradable examples are known. There are three uncirculated Mountain $20s in private hands, and any lustrous, original coin would qualify for the condition census. In 2006, numismatists Andy Lustig, Ron Karp, and David J. McCarthy discovered a proof striking of the Mountain $20 that apparently traced its provenance back to Emanuel Henry Gruber.