The following information is from my eBook on Type One Liberty Head Double Eagles at http://doubleeaglebook.com/
In 1860, Anthony C. Paquet, the mint’s assistant engraver, produced a new reverse for the double eagle. It was characterized by tall lettering and a very narrow rim. By the earliest part of 1861, it was decided that this design would not wear well, due to the narrowness of the border. A telegraph was sent to the San Francisco mint ordering a return to the old style Longacre reverse. This telegraph appears to have taken a considerable amount of time to reach the mint and by the time it had, $385,000 worth of the new reverse 1861-S double eagles had been struck and released into circulation.
The 1861-S Paquet reverse double eagle was a mostly-forgotten issue until it was “rediscovered” in the 1930’s. A number were found in European holdings of United States gold coins and many were repatriated back into the American coin market. Today, this issue is rare but it is still considered an important issue within the Type One series which is collected alongside the “regular” 1861-S double eagle. This variety was clearly made to circulate and it is unquestionably a regular issue
STRIKE: The obverse shows a quality of strike which is not much different from that seen on the regular issue 1861-S double eagles. The hair is weak with little definition seen on the curl. The hair at the top of the head and the bow are soft. The stars some radial lines definition but they are not as sharp as on the 1861 Philadelphia double eagles. The central details on the reverse are sharp with some minor weakness noted on the horizontal stripes in the shield and on the tail feathers. Due to a lack of a broad border, the reverse may show uneven wear. On coins which grade About Uncirculated-50 and higher, the centers may appear sharp while the tops of the letters have more wear than generally seen on coins in this grade range.
SURFACES: The surfaces are almost always heavily abraded. Ironically, the obverse tends to be more heavily abraded than the reverse; this is “ironic” as the design was changed due to supposed wear and rim problems with the reverse that would lead to extensive marks after a short stint in circulation. I have seen a few with mint-made black spots and a small number with areas of roughness in the planchet.
LUSTER: It is hard to determine what the original luster on this issue should look like as there are so few known which have not been tampered with in some fashion. On the few that grade high enough to show luster, it tends to be soft and satiny with a slightly grainy texture.
COLORATION: The natural coloration is a medium to deep green-gold with some rose or yellow-gold tinges. This is a very rare coin with totally natural color and most have been cleaned or dipped.
EYE APPEAL: This issue is characterized by decidedly below average eye appeal. Most are not well struck, have heavily abraded surfaces and are unevenly worn, especially on the reverse. Any 1861-S Paquet reverse with good eye appeal is very rare and a CAC-quality example should command a premium in excess of 25%, if not more.
INTERESTING VARIETIES: Some are known which show no period after the D in TWENTY D. This is either the result of a filled die or die wear. While rare, this variety is not considered significant. The mintmark is very small and it appears jammed between the tail feathers and the NT in TWENTY.
PROOFS: No proofs were struck.
HOARDS: A single example, graded AU58, was found in the S.S. Republic. In the 1950’s and 1960’s, examples were regularly found in Europe and in other overseas sources of American gold coins. Today, it is very unusual for an 1861-S Paquet to be located in any overseas source.
BUYING TIPS: This is the most expensive Type One double eagle that many collectors will make an attempt to purchase. It is misleadingly available in About Uncirculated grades and, in my opinion, most in AU50 and AU53 holders are noticeably overgraded. Take your time when buying this issue and wait for a coin which has comparatively good eye appeal. CAC has approved seven 1861-S Paquet double eagles as of 10/14 (four in AU53 and none higher) which shows that while very hard to find with good eye appeal, locating the right coin will not prove impossible.
AUCTION RECORD: The current record for this issue is $223,500 which was set by a PCGS AU58 sold as Heritage 4/14: 5807.
FINEST KNOWN: There are four PCGS AU58 examples known but none of these is clearly the best. If I had to select one, I would go with Heritage 4/14: 5807 which is a solid coin for the grade.
TOTAL KNOWN: 150-200
Very Fine: 60-800
Extremely Fine: 65-85
About Uncirculated: 25-35
POPULATION FIGURES: As of the beginning of 2015, PCGS had graded 20 in AU50, 12 in AU53, four in AU55, and four in AU58 for a total of 40 coins in About Uncirculated. NGC had graded 15 in AU50, 10 in AU53, 12 in AU55, and 10 in AU58 for a total of 47 in About Uncirculated. These figures are significantly inflated, especially those from NGC. CAC has approved just seven examples, the highest are four examples in AU53.
PERFORMANCE SINCE 2002: In the current market, a choice Extremely Fine example of this date (equivalent to EF45) is worth $65,000-70,000+. When the first edition of this book was published in 2002, the same coin would have sold for $15,000-20,000. In the current market, an average quality About Uncirculated example of this date (equivalent to AU53) is worth $75,000-85,000+. When the first edition of this book was published in 2002, the same coin would have been worth $25,000-35,000. The price performance of this issue has been excellent and part of this has to do with prices, in 2002, being undervalued relative to actual rarity. After peaking in 2008, prices dropped in 2009-2012 but have begun to rise in 2013 and seem strong at current levels.
COMMENTS: The popularity of the 1861-S Paquet reverse double eagle has soared since the first edition of this book was published in 2002. It is now one of the most desirable Type One issues, partially due to its rarity and partially due to its great background story. It is scarce in all grades although not as much so as I originally believed. Most are in the Extremely Fine-40 to About Uncirculated-50 range and both services tend to overgrade this issue. Accurately graded About Uncirculated-50 pieces are rare and in About Uncirculated-55 this is a rare coin. I have seen three in About Uncirculated-58 holders which I felt were accurately graded.
David Akers (1975/88):
The 1861-S Paquet is the rarest Liberty Head Double Eagle from the San Francisco Mint. Its only real close competitor for that distinction is the 1866-S No Motto but, in my opinion, there are more of the latter in existence than there are 1861-S Paquets. In high grade, the 1861-S Paquet is extremely rare and, to the best of my knowledge, it is unknown in full mint state. I have seen only two specimens I graded as high as AU-50 and nothing even close to Unc. As a general rule, this date is usually grossly overgraded and even in strict EF condition it is seldom available. In my experience the majority of 1861-S Paquets are well worn, VF being typical, and they are almost always very heavily abraided.