This page was written in 2015, the 68th year of Queen Elizabeth's reign. Back in 1972, she was up to 25 years, and the Cayman Islands, a dozens of other locations, honored her silver anniversary with special mintings of special coins and medals. This one in particularly beautiful.
There are two:
SILVER $25: 1.527 troy ounces silver
GOLD $25: 0.222 troy ounces gold
The value of these coins depends on their base value, or BV. To compute BV, multiply the current price of precious metal by the weight of precious metal. Today's silver price is $14 US dollars per troy ounce and today's gold price is $1057 US dollars per troy ounce. But tomorrow, silver and gold will trade at different prices, so be sure to look them up.
BV for silver is 14 x 1.527 = $21 and for gold 1057 x 0.222 = $235. The price of these coins is somewhat above BV due to collector demand, as follows.
circulated: BV + $5
fully uncirculated: BV + $10
circulated: BV + $10
fully uncirculated: BV + $30