The following information is from my eBook on Type One Liberty Head Double Eagles at http://doubleeaglebook.com/
The 1861-O was the last double eagle struck at the New Orleans mint until this denomination was resumed in 1879. It is numismatically significant as the final Type One issue from this mint, and it is historically significant due to the fact that it was struck under three different authorities: the Union, the State of Louisiana, and the Confederacy. It is believed that the mintage figures for each of these breaks down as follows:
Union: 5,000 struck from January 1 to January 26, 1861
State of Louisiana: 9,750 struck from January 26 to May 31, 1861
Confederacy: 2,991 struck after June 1, 1861
Is there a way to determine which coins were struck under which auspices? With the assistance of collector Dr. Joseph Gaines, I have devised a theory which, at the very least, explains which coins were made by the Confederacy. For more information, see below.
STRIKE: This is the worst-struck New Orleans double eagle,, and it is one of the hardest Type One issues to find with acceptable details for the grade. The obverse shows considerable weakness on the hair of Liberty with little definition visible on the curls around the face and below the ear. The hair at the top of the head is very weak and the bow appears to be incomplete. The obverse stars tend to be flat with the ones at the right showing more detail than those over the head or to the right. The date tends to be weak (see below) with most examples not detailed on the lower parts of all four digits. The reverse is sharper but it is always found with some degree of weakness on the wing tips, tail feathers, and the neck of the eagle.
SURFACES: Virtually all known 1861-O double eagles show deep, extensive marks on the obverse and reverse. This date appears to have seen extensive and rough circulation with many survivors showing signs of having been mishandled with rim bruises, scratches, and scrapes on the surfaces. The few that exist with clean surfaces are very rare and sell for strong premiums over “typical” coins.
LUSTER: Some 1861-O double eagles are prooflike with a good degree of reflectiveness present. Others are more satiny in texture. The majority have been cleaned and dipped enough times that the original reflectiveness is no longer intact and this has led to a “washed out” appearance.
COLORATION: The range of natural coloration extends from a medium green-gold to a lighter yellow-gold. It is extremely hard to find an 1861-O with nice natural color as most have been cleaned or dipped.
EYE APPEAL: This is one of the more difficult Type One double eagles to find with good eye appeal. Most are softly struck, unoriginal and heavily marked. Pieces with above-average eye appeal are very rare and in strong demand.
INTERESTING VARIETIES: The 1861-O double eagle is thought to have been created from a single pair of dies. The obverse is usually weakly struck. The majority of coins (approximately 75%) have a weak date with the lower portions of the 186 and sometimes the final 1 weak or nearly absent. The obverse and reverse appear to have been lapped, giving the surfaces a slightly prooflike appearance. In the latest state of the weak die coins, it appears that a mint employee scribed a series of lines into the die, partly restoring the base of the 8. A good example of this die state is Bass II: 807 (Bowers and Merena, May 2000).
There are also a number of strong date coins which show an obverse die crack that begins at the rim atop the denticles over the second star extending to near the chin of Liberty. A branch of this crack also extends upwards to the third star. The strong date coins show no repunching or remnants of the scribe lines seen on the later die state(s) of the weak date coins.
Three sets of dies were sent to the New Orleans mint in December 1860 for use to strike double eagles and it has always been assumed that only a single pair was used. The date logotype and the position for the weak and strong date coins is exactly the same. Many researchers have assumed that the weak date coins are connected with the Confederacy. They show no evidence of the obverse die crack as seen on the strong date coins and this suggests that a second die may have been used. The obverse crack is too deep to have been completely removed by die lapping. It is not clear whether the weak or strong date coins were struck first. It is certainly plausible that the weak date coins were made first, the die was repaired, the defective die was removed from service, and then the strong date coins were made; first with no defects and then later with the obverse crack. Another possibility exists as well: the obverse die was repaired and was strengthened by a mint workman. This does not appear likely as the New Orleans mint probably did not have the date punches it needed to do this work in 1861, and the weak date coins do not show the aforementioned crack.
After looking through hundreds of auction catalogs and studying images of 1861-O double eagles offered for sale, Joe Gaines and I have determined that around one-fifth of the coins offered had a strong date and showed the obverse crack. When one considers that the Confederacy is said to have struck approximately 17% of the original mintage of this issue (2,991 of the 17,741 struck) this is almost exactly the percentage of coins which exhibit the strong date with the crack. We believe that these coins are the ones made by the Confederacy.
PROOFS: No proofs were struck.
HOARDS: Two AU58 examples were graded by NGC as part of the S.S. Republic treasure. Some 1861-O double eagles in medium grades appear to have entered the market in the early 1990’s as part of a huge bank hoard which was found overseas.
BUYING TIPS: Gradeflation has affected this date more than nearly any other New Orleans Type One double eagle. Virtually every 1861-O double eagle in a third-party holder is overgraded; you want to look for a coin which has the best possible eye appeal for its assigned grade
AUCTION RECORD: The current auction record for this date is $146,875, which was set by Heritage 1/14: 5527. This coin was graded MS60 by NGC.
FINEST KNOWN: The finest known is likely an MS62PL which has been graded by NGC. I have never seen this coin and it has never appeared for sale at public auction.
TOTAL KNOWN: 150-175
Very Fine: 50-60
Extremely Fine: 65-70
About Uncirculated: 32-40
POPULATION FIGURES: As of the beginning of 2015, PCGS had graded just two coins in Uncirculated and both were MS60. NGC had graded three in MS60, one in MS61, and one in MS62PL for a total of five. CAC has approved just 11 examples, and none are Uncirculated.
PERFORMANCE SINCE 2002: In the current market, a choice Extremely Fine example of this date (equivalent to EF45) is worth in the $30,000-40,000 range. In 2002, a similar coin would have sold for $9,000-11,000. In the current market, a nice About Uncirculated example of this date (equivalent to AU55) is worth in the $65,000-75,000 range. In 2002, a similar coin would have sold for $20,000-25,000. The 1861-O has shown exceptional performance with nice coins rising in price at least 3x to 4x. I would attribute at least some of this to the publication of the first edition of this book in 2002.
COMMENTS: The 1861-O has a more broad level of demand than any other Type One double eagle due to its Civil War association. It is probably a bit less rare in terms of overall rarity than one might expect, but it is extremely hard to locate with natural color and choice surfaces. Most survivors are in the Extremely Fine-40 to About Uncirculated-50 range and show clear evidence of extensive circulation coupled with numismatic abuse.
David Akers (1975/88):
The 1861-O is the last Double Eagle from the New Orleans Mint until 1879. Coins were both before and after the Confederacy took control of the Mint but it is impossible to state with absolute certainty which coins were struck by the Federal Government and which were struck by the Confederacy. The 1861-O is rare but obviously not nearly as rare as the 1856-O, 1854-O, 1855-O or 1860-O. It is closest in overall rarity to the 1857-O and 1858-O (a bit less rare than either) and it is decidedly rarer than the 1850-1853 O-Mint issues. The 1861-O is very rare in AU and virtually all known specimens grade only VF or EF. I have not personally seen a strictly uncirculated specimen: the best I've encountered was a choice AU-55 and I have seen three in that grade. The Miles specimen was called uncirculated and there was also a specimen graded uncirculated in Stack's 1946 Deetz Sale. Whether or not the Miles or Deetz coins were really Unc. I cannot say since I have not seen them. Most 1861-O Double Eagles are partially or fully prooflike and quite well struck although the bottom part of 186 in the date is usually weak from die wear.