They were prepared in three strikes : two presentation coins in 1834 for the diplomatic travel of Edmund Roberts in Asia, two additional coins in early 1835 for an an extension of the same trip and a final set of four in 1835 for the archives of the Philadelphia Mint.
The reason for the later Class II and Class III restrikes made between 1857 and 1860 is not clear.
The sixth specimen in the Class I roster is graded PR62 by PCGS. It was twice sold by Heritage, for $ 3.7M including premium on April 17, 2008 and for $ 3.9M including premium on August 9, 2013. It is now listed as lot 4003 by Heritage in Long Beach on June 14.
I summarized the reason for its rarity as follows before the 2013 sale.
The dollar is a symbol of money and the East is a dream of wealth. During the presidency of Jackson, Edmund Roberts became ambassador at large of the United States to the East.
In 1834 Roberts was responsible for presenting the richest monarchs with a complete series of the then legal US coinage from its current or last year.
When this decision was made nobody appreciated that this special set was to include for its credibility a coin that had never existed : the 1804 silver dollar. Its production had stopped after that date and all the coins from that ultimate year had been made with 1803 dies.
The 1804 dollars prepared for Roberts's diplomatic mission were for these reasons the first to use that face date, with a delay of thirty years.
Please watch the video shared by Heritage. The image below has been downloaded a few years ago from Wikimedia.
SOLD for $ 2.64M including premium