BG- 508, 1854 California Gold Rush Circulating Fractional Gold $1, Liberty Octagonal NGC MS64PL R4+

Here's an opportunity to acquire a more affordable--and stunningly attractive--piece in the extensive California Fractional Gold series. It was crafted and struck by the prolific San Francisco firm of Frontier, Deviercy & Co. NGC has graded 12 examples as Prooflike. There are 4 in MS64PL with 1 finer. PCGS has attributed only 2 of this variety as PL. Both carry the grade of PCGS MS62PL.

How were such coins struck? Frontier, Deviercy & Co. had a German or French coin screw press from the 1830s. (The image of the screw press is below.) A detailed report in Coinweek.com explains the process:

Mechanically, this screw type press is operated by a long, hand-thrown centrifugal rod at the top, which causes a thick 2″ screw to be pressed down. As the screw presses down it pushes on a square shaped length of iron that moves up and down and imposes considerable force on the hammer die which is mounted at its base. An ingenious feature is the square shape of the iron driving rod, this mitigates the rotational force from the screw action that would otherwise torque the hammer die and cause uneven striking.

The direction of the hammer die is straight downward where it meets the planchet that is held in place by a collar and supported on the lower die, thus striking the impression into the planchet to create a coin.

Photo: Stacks January 2011 New York Americana Sale.