The 1856 is a far more attainable date than the 1855, and thus is always in demand from
Type set
A collection consisting of one coin of each type and possibly variety
type set collectors. While it is actually quite a common date, probably being the most common Sydney mint type, this demand has ensured that its value has kept up with the scarcest of the Type II Sydney Mint half sovereigns. Demand typically resides around the Fine - VF range at which the date is actually quite scarce relative to the rest of the series. In the upper grades, the coin is relatively common with many top-quality examples originating from the Indian
Hoard
A large number of coins found from a single source that have never before reached the collector market
hoard leading me to believe that it is quite overrated.
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