1951 was the golden anniversary (50th) of the federation of Australia. A florin (2 Shillings) was released to commemorate the event. The obverse bears the usual Paget portrait of George VI while the reverse bears a design by William Leslie Bowles, a Victorian sculptor. His design was one of several considered by the treasury department at the time of the coin's release. It depicts a sword crossed with a scepter. Above the cross is what appears to be the Imperial State Crown of Great Britain while below it is the seven pointed Federation Star of Australia. Behind the sword and scepter is the Southern Cross, the constellation known as Crux. On the left of the reverse is the year 1901 and the right 1951 representing the 50 years since the federation of Australia.
1 Florin (2 Shillings): 28.5mm diameter, 0.1818 troy ounces silver.
Typical catalog values run like this:
worn: BV (bullion value)
average circulated: $BV
well preserved: BV + $5 US dollars
fully uncirculated: BV + $15
BV changes continuously. Today's silver price is $18.61 US dollars per troy ounce silver price (look it up at kitco.com), so BV = 0.1818 x 18.61 = $3.38.