The following information is from my eBook on Type One Liberty Head Double Eagles at http://doubleeaglebook.com/
The 1865 is the final Type One double eagle produced at the Philadelphia mint. It is more available in all grades than the 1862-1864 issues. It was formerly rare in Uncirculated but it has become far more available due to the discovery of numerous coins from the S.S. Republic.
STRIKE: Many of the non-shipwreck 1865 double eagles are somewhat weakly struck on the curls around the face of Liberty. This date tends to be a bit less well struck than the 1864 and the hair at the top of the head is less detailed than on the 1864. The obverse stars are sharp and often show full radial line detail. The obverse border from 2:00 to 6:00 may sometimes show slight weakness. The reverse is well struck with slight weakness confined to the wing tips and tail feathers. A network of fine cracks joining the tops of the lettering is seen on some coins.
The 1865 double eagles from the S.S. Republic are well-struck and show nearly complete definition at the centers and borders.
SURFACES: The 1865 double eagle shows numerous small ticks and abrasions on its surfaces, as do nearly all Type One double eagles. The average non-shipwreck 1865 is very noticeably abraded and, for some reason, these marks tend to be more noticeable on the obverse than on the reverse. Still, it is easier to find a relatively clean example of this date than it is for the 1862-1864 Philadelphia issues.
The 1865 double eagles from the S.S. Republic have excellent surfaces. Many of the higher grade pieces (MS63 and above) are only slightly marked with a few stray scuffs seen in the fields.
LUSTER: The luster is frosty and similar in appearance to that seen on the 1864 double eagle. Original, higher-grade coins display good luster but the typical 1865 has impaired luster and has been dipped or cleaned. A few semi-prooflike coins are known but these tend to be very heavily abraded.
The 1865 double eagles from the S.S. Republic have excellent luster. In fact, if just a few were known, they would be almost impossible to distinguish from non-shipwreck coins. The luster on these pieces is frosty in texture with a slightly satiny appearance.
COLORATION: The natural coloration is medium yellow-gold or slightly deeper rose and orange-gold. Examples with natural color are scarce but are more plentiful than the 1862-1864 Philadelphia issues.
The 1865 double eagles from the S.S. Republic have rich yellow-gold or light green-gold hues which are very attractive.
EYE APPEAL: Before the discovery of the shipwreck coins, the typical 1865 double eagle had below average eye appeal. Now, it is possible to acquire an exceptional Uncirculated example which is reasonably clean, very lustrous and which has pleasing natural color.
INTERESTING VARIETIES: There are at least three interesting varieties known.
Normal Date. This variety is very common.
Repunched Date. The original punch was too high and far to the left. It was subsequently corrected, but clear traces of the 186 can be seen under light magnification. This is an interesting variety that some specialized collectors pursue, but it does not sell for a premium. It is scarce.
Misplaced Date. Faint traces of the base of an 18 can be seen in the denticles below the 65 in the date. This variety was first discovered by NGC when examining coins from the S.S. Republic. It appears to be rare, and it should likely sell for a premium as it becomes better know.
PROOFS: The 1865 has the lowest mintage figure of any Type One double eagle produced during the 1860’s. Only 25 were struck. There are around seven or eight known in total with two of these in the Smithsonian/Mint collection. Unlike some of the other dates from this era, the 1865 is not often seen with intense “black and white” contrast and only one distinct example has been accorded an Ultra Cameo or Deep Cameo designation by the grading services. CAC has approved two proofs, an MS64 and an MS66.
As of the beginning of 2015, PCGS had graded three in PR64, two in PR64 Deep Cameo, one in PR65, and one in PR65 Deep Cameo for a total of seven. NGC had graded three in PR64, two in PR65, and one in PR66 Ultra Cameo for a total of six. These figures are inflated by resubmissions.
The current auction for a Proof of this date is held by Heritage 4/14: 5847, graded PR66 Ultra Cameo by NGC, which realized $440,625. This same coin, then graded PR65 Deep Cameo by PCGS, sold for $264,500 as ANR 8/04: 1102.
HOARDS: Hundreds of 1865 double eagles were found in the S.S. Republic treasure, and this includes 271 Uncirculated pieces which were first graded by NGC. Small groups of circulated 1865 double eagles are still found in Europe.
BUYING TIPS: Thanks to the S.S. Republic, locating higher grade examples of this date is much easier than when the first edition of this book was published in 2002. If a collector wants a non-shipwreck coin, he should be able to locate a nice circulated example without much difficulty. Higher grade pieces from the shipwreck generally have excellent eye appeal and the collector can be choosy when selecting one of these pieces for his set.
AUCTION RECORD: The auction record for a business strike 1865 double eagle is $88,125 which was set by a PCGS MS65 coin offered as Heritage 4/13: 4575.
FINEST KNOWN: The finest known is an NGC MS66 from the S.S. Republic which I sold to a New England collector in 2014. It set a record price for a business strike of this date.
TOTAL KNOWN: 2900-1200+
Very Fine: 200-250
Extremely Fine: 200-300
About Uncirculated: 200-325
POPULATION FIGURES: As of the beginning of 2015, PCGS had graded six in MS60, nine in MS61, 11 in MS62, 10 in MS63, five in MS64, two in MS64+, and one in MS65 for a total of 43 in Uncirculated. NGC had graded three in MS60, 37 in MS61, 59 in MS62, 109 in MS63, 85 in MS64, 23 in MS65, and one in MS66 for a total of 240 in Uncirculated. These figures are inflated by resubmissions. CAC has stickered 48 Uncirculated examples: four in MS61, seven in MS62, 18 in MS63, 11 in MS64, seven in MS65, and one in MS66.
PERFORMANCE SINCE 2002: In the current market, a choice About Uncirculated example (equivalent to AU55) is worth $3,000 to $4,000. In 2002, when the first edition of this book was published, a similar coin was worth around $1,500-2,000. In the current market, a nice Uncirculated example (equivalent to MS62) is worth $14,000-16,000. In 2002, a similar coin was worth $9,000-11,000.
This last set of figures is a remarkable testament to the strength of the Type One market. In 2002, the combined PCGS/NGC population for this date in MS62 was 15 with three finer. As of the end of 2014, the combined PCGS/NGC population is recorded as 71 in MS62 with 237. One would have expected the value of an MS6 to drop dramatically but, instead, prices have risen. This is, obviously, due to a strong increase in demand for Type Ones. I expected this date to drop considerably in value after the 271 Uncirculated pieces were located in the S.S. Republic, but I didn’t anticipate the depth of this market.
COMMENTS: As recently as a decade ago, if you wanted an 1865 double eagle in Uncirculated grades, the chances were good that you were not going to locate one or, if you did, it would be a scruffy, low-end piece. But the S.S. Republic treasure forever changed the rarity complexion of this issue. Nearly 300 attractive Uncirculated examples were found including some which are the most visually impressive Type One double eagles of any date that I have seen. These have been well-distributed and are not overhanging the market but they appear with enough regularity that the collector should be able to buy a truly nice 1865 without a great effort.
Much of what we know about the 1865 $20 has changed since David Akers wrote about them decades ago. The most significant development was the discovery in 2003 of approximately three hundred 1865 $20 gold pieces in the shipwreck of the S.S. Republic. After conservation, numerous Mint State examples swelled the population and the condition census. Despite the addition of hundreds of coins to the known populations, the 1865 still conforms to Akers' conclusions of long ago -- the 1865 $20 remains rarer than all the dates cited by Akers (1855, 1856, 1857, 1858, 1859, 1862, 1863, and 1864) and it remains less common than the 1854 and the 1860. However, Akers' comments on condition are no longer relevant. Now, every 1865 $20 in the PCGS Condition Census grades at least MS64 and the finest examples rate out at MS65.
David Akers (1975/88):
The 1865 is a scarce date but it is not as rare as the 1855-1859 P-Mint issues or the 1862, 1863 and 1864. It is, however, more rare than the 1854 or 1860. When available, the typical 1865 is VF or EF although an occasional AU can also be located. In full mint state, the 1865 is rare and choice (63) quality uncs are very rare. I have never personally seen a gem 1865 and so I cannot say for sure whether or not one exists.