Extremely Rare 1853 U.S. Assay Office Twenty, .884 Thous., MS63
1853 $20 Assay Office Twenty Dollar, 884 Thous. MS63 PCGS.
K-17, Low R.7. Nitric acid and sulfuric acid are among the few
known chemical substances that can dissolve gold, or "part" it from
the various alloys with which it is normally bonded when found in
its natural state. The lack of parting acids was a chronic problem
both for the U.S. Assay Office of Gold, as well as later for the
fledgling San Francisco Mint.
Single Finest at PCGS and Tied for Finest Certified
In October 1852 the San Francisco customs collector received a letter from the Treasury Department, essentially telling him to accept only U.S. federal gold coins that conformed to the Mint Act of June 25, 1834--.900 fine gold. California gold coins of any other standard were essentially devalued, as they were of lesser commercial utility. The concern in Washington was that nonconforming gold coins would enter world commerce, damaging U.S. prestige overseas. In reality, the Assay Office pieces of lesser fineness were actually compensated by assayer Augustus Humbert with an increased weight--a fact that the Washington insiders likely did not know.
The local merchants met with the customs collector, absolving him of personal responsibility so he could accept .900 fine coins without the proper copper alloy mix, something that was essentially unproducible in California at the time.
But the parting acids were on backorder, and Humbert made the decision to strike emergency ten and twenty dollar pieces, first with the .880 fineness and then with the .884 fineness, as Kagin says "in total defiance of the August 31, 1852, law. [Humbert] hesitated as long as possible, and then commenced striking the lower fineness coins from February 23 to March 1, 1853. The new parting acids arrived before too many pieces were struck and immediately the .884 THOUS. pieces on hand were remelted and coined into .900 THOUS. coins."
That remelting accounts for the extreme rarity of the few .884 THOUS. survivors, and the present piece is not only the single finest certified at PCGS, it is one of only three Mint State pieces graded at that service (12/07) along with one MS60 and one MS62 piece. NGC has certified seven pieces, the finest also an MS63. The surfaces are a deep greenish-gold, with a somewhat prooflike appearance and numerous small contact marks consistent with the grade. This coin presents a fine opportunity for some fortunate collector to obtain what is--barring the fifty dollar slugs--the rarest of the U.S. Assay Office pieces. Listed on page 355 of the 2008 Guide Book. (NGC ID# ANHC, PCGS# 10010)
Service and Handling Description: Coins & Currency (view shipping information)
Sales Tax information | PCGS Guarantee of Grade and Authenticity | Terms and Conditions
Bidding Guidelines and Bid Increments
Glossary of Terms
Buyer's Premium per Lot:
15% of the successful bid (minimum $9) per lot.
Floor auctionsOpen for bidding: (View All)
Ends on 12/03/2015
Fine & Rare Wine
Ends on 12/04/2015
Jewelry & Timepieces
Ends on 12/07/2015
Ends on 12/08/2015
Ends on 12/09/2015
Ends on 12/10/2015
Ends on 12/10/2015
World & Ancient Coins
Ends on 12/11/2015
Civil War & Militaria
Ends on 12/12/2015
Arms & Armor
Ends on 12/13/2015
Comics & Comic Art
Ends on 12/13/2015
Ends on 12/18/2015
sold in the last year
- Past Auction Values (prices, photos, full descriptions, etc.)
- Bid online
- Free Collector newsletter
- Want List with instant e-mail notifications
- Reduced auction commissions when you resell your
Learn about consigning with us
Perhaps the best part of my consigning experience has been my realization that all consigners, large or small, receive the same personal service and attention to detail at Heritage.View More Testimonials