NGC provides submission guidelines and mintage information for bullion Silver Eagles struck at various Mint facilities, 2011 to date
Numismatic Guaranty Corporation (NGC) will attribute 2011 to 2017 bullion American Silver Eagles by the US Mint facility that struck the coins provided they are received by NGC in a sealed US Mint box. The attributions provide a more advanced way to collect the popular series, which has been issued annually since 1986.
Bullion Silver Eagles are sold by the US Mint in sealed 500-coin boxes, commonly called “monster boxes” by collectors. These coins do not have mintmarks, but as a result of its research–now confirmed by the Department of the Treasury–NGC can conclusively identify the mint facility that struck the coins contained in each 2011 to 2017 monster box.
The methods used by NGC to identify the mint facility are described in the following chart.
* As of March 20, 2017, per the US Mint FOIA response
No bullion Silver Eagles were at the Philadelphia Mint in 2014 or at the San Francisco Mint in 2015.
Attribution by NGC
NGC will label these coins with a mintmark in parentheses and expressly state the mint facility that struck the coin. The mintmark is in parentheses to indicate that it is not actually present on the coin. For example, a coin struck at the San Francisco Mint in 2017 will be described as a “2017(S) EAGLE S$1” with the text “Struck at San Francisco Mint” above. These descriptions can appear in combination with NGC Releases Designations, authentic hand-signed labels and other special NGC labels.
Because the Mint production facility can be identified only by the sealed “monster boxes,” NGC’s attribution of these coins is limited to bulk submissions of original, sealed monster boxes. Dealers are encouraged contact NGC for further instructions about this service.
Facing overwhelming demand for bullion-issues American Silver Eagles, starting in 2011, the US Mint supplemented production at West Point by striking coins at San Francisco. Although these coins do not have mintmarks, NGC was able to attribute coins submitted in sealed packaging to their Mint of origin. Those boxes were sealed in green “monster boxes” with nylon straps indicating the Mint where they were struck. These straps were used through 2014.
Beginning in 2015, the Philadelphia Mint was also employed to strike bullion American Silver Eagles, but the US Mint still sealed all monster boxes with “West Point Mint” straps. Only a numbering system and bar code stickers were used to mark and identify individual boxes from 2015 to date. In 2016, a strap labeled “United States Mint” was adopted for use with all coins.
Owing to minor variations in box appearance and coin quality, NGC graders long suspected that multiple Mints continued to be involved in the production of Silver Eagles. Early this year, NGC reached out to Coin World to inquire if they had information regarding the mint facilities being used for Silver Eagle production. With no information publicly available, NGC and Coin World independently filed Freedom of Information Act requests for additional information regarding Silver Eagle production facilities and how to decipher box codes.
A new series rarity is revealed! The 2015(P) Struck at Philadelphia Silver Eagle deserves a special mention because, at only 79,640 coins struck, it is by far the rarest bullion American Silver Eagle in the series, which has been issued annually since 1986.
Populations figures for American Silver Eagles attributed to individual production facilities can be viewed in the NGC Census. They are visible by clicking the varieties button under each applicable date.