J-270 1857/1860 $2.50 NGC PF62 RB CAC. R-7-. Fantasy mule: 1857 Liberty Head obverse over wreathed  Quarter Eagle reverse. This double dated, unusual, proof pattern mule shows significant mint luster and coppery-red color remaining in protected areas of both sides. Despite the presence of a couple of dark spots, one on the obverse date and the other on the S in DOLLARS on the reverse, the coin is fully uncirculated. Its grade of PF62 Red and Brown is confirmed by CAC, indicating that the piece is of premium quality for the grade range. The strike is above average with almost full details seen on Libertys hair and the design features of the reverse.

Often the US Mint thinks of changing designs for coins in circulation. In earlier times, the Chief Engraver was responsible for proposing design changes through the production of pattern coins. These test pieces allowed the Mint officials to see how the proposed designs looked and struck up. They also allowed the officials to test new metals and new alloys. From time to time Mint officials created fantasy coins, which included unexpected pairings of mismatched dies. They also included restrikes of rarities and coins that were restruck outside the mint from discarded dies.

The J-270 pattern is a fantasy mule with two different dates. The obverse die was used to strike the J-186 pattern cent dated 1857 and the J-189 quarter eagle pattern also dated 1857. The portrait of Liberty is similar to the one used on nickel three-cent pieces of 1865 to 1889. The reverse die is dated 1860 and denominated 2 dollars. It consists of an open wreath enclosing the denomination and the date.

After the death of Christian Gobrecht on September 16, 1844, James B. Longacre was appointed Mint Engraver. He remained in that post until his death in 1869. Except for those of Anthony Paquet, Longacre was responsible for the pattern designs that were made during his tenure. When Longacre first came to work at the Mint, he was opposed by Franklin Peale, the Chief Coiner. Peale was probably responsible for some blundered dies that Longacre was criticized for making. Peal was involved in a private, illegal medal manufacturing business using Mint facilities. He was concerned that this new political appointee would interfere with his business, and he resisted Longacres appointment as Chief Engraver. In the end Peale was found out and fired in 1854. Longacre flourished in his position and was responsible for creating many new designs including the Indian Head cent, the Two-cent piece, the Shield nickel, the Liberty Head gold dollar, the Indian Princess gold dollars, the Three dollar gold piece, and, the Liberty Head double eagle.

The J-270 1857/1860 pattern has a low 7 rarity rating, which means that there are 7 to 12 specimens known today. In its population report, PCGS shows this piece to be unique in RB condition. At CAC, as of December 2011, the population is 1 with none better.