Thought I'd present something a little different for my 500th post...
The modern US non-circulating legal tender (NCLT) commemorative series is not one that draws much attention from the community of error coin collectors. Though the series is now in its 31st year, it hasn't been the source of a significant number of production "anomalies" such as off-center strikes, broad strikes, coins struck on clipped planchets and double- and triple-struck coins. Such errors are unheard of within the NCLT commemorative series, largely owing to the fact that the Mint can impose stricter quality control measures on these limited mintage coins vs. those that are produced in the hundreds of millions on high-speed presses. (It also doesn't hurt that if a mis-struck coin doesn't fit into its designated plastic capsule, it's very easy to spot!
Back in 1989, however, word began to spread that a rather spectacular commemorative error was created at the Denver Mint -- an unknown number of the 1989-D Congress Bicentennial commemorative silver dollars (uncirculated) were rumored to have been struck with the reverse die rotated 180°. The "king" of the rotated die errors in a NCLT coin!
How can a rotated die strike occur? Possibilities include: 1) the die being set into the press incorrectly; 2) the screws that hold the die shaft in place coming loose and allowing the die to rotate; and 3) the shaft of the die breaking and allowing free rotation of the die head.
Coins, tokens and medals are struck in either "coin alignment" or "medal alignment." A piece struck in coin alignment indicates that if you view one sign of the piece in its proper orientation, rotating the piece vertically will present the opposite side in the proper "right side up" orientation as well. With medal alignment pieces, the opposite it true -- rotating the piece vertically will present the opposite side upside down. Pieces struck in coin alignment have one die oriented "up" and the other "down" in the press. For medal alignment pieces, both dies are oriented either "up" or "down." As can be guessed from the terms, coins are typically struck in "coin alignment" and medals in "medal alignment." US coins
are struck in coin alignment. So, a US coin with one die rotated a full 180° from its proper position is considered a major error coin.
The exact number of medal alignment Congress dollars is unknown, I have seen estimates range from about 50 to 100+. I have spoken with a highly regarded error coin dealer (Fred Weinberg) and a US commemorative coin expert/dealer (Anthony Swiatek) and they each estimate the population to be about 50 vs. anything much higher. In justifying his position, for example, Fred told me he has handled less than 10 unique examples of the coin in all the years they've been known to the hobby -- a small number considering his widely known area of specialization and the constant funneling of important errors to him by other dealers.
There can only be one "discovery" coin for a newly discovered error. I was fortunate enough to have the opportunity a few years ago to purchase the discovery coin of the 1989-D Congress commemorative error (i.e., the first coin to be examined and certified by CONECA [the Combined Organizations of Numismatic Error Collectors of America] as a 180° rotated die example); the coin came with the CONECA certification letter.
As seen below, the coin is certified by PCGS
as MS-68 (I don't know why it's not a "69".). It is housed in a PCGS
"Signature Holder" that has an accompanying cloth drawstring bag. "Signature Holders" were promoted by PCGS
a number of years back as a deluxe holder for coins of special note. The holder does not appear to have gained much favor within the hobby, however, as the option has been discontinued by PCGS
and few coins are to be found in them.
I realize it's difficult to "see" a 180° rotated die error without having the coin in hand, but hopefully your imagination will allow you to enjoy the images presented.
I've enjoyed pulling this piece out on occasion for show-and-tell at the local coin clubs, so I thought it would be fun to share it with CCF as well.
Enjoy!1989-D Congress Bicentennial Silver Dollar - Obverse1989-D Congress Bicentennial Silver Dollar - Rotated ReverseNote: Design should be upside down with the holder in this orientation.