To find the value of an Elizabeth II DG REG FD coin, note the coin's denomination and year, then check it against a database such as the one at UCoin.net. UCoin.net contains approximate values for British coins from various years. A commemorative silver 25 pence coin was released in 1977 to celebrate Queen Elizabeth's Silver Jubilee. The value of these coins depends on the current price of silver.
Most of the commemorative coins from 1977 were made from copper nickel. The silver coin is worth more, as it contains 0.841 troy ounces of silver. To calculate the coin's approximate value, multiply the price of silver by 0.841.
"Elizabeth II DG REG FD" is a common inscription on British coins, and it appears on many denominations over the years. "DG REG RFD" is an abbreviation of "By the Grace of God, Queen and Defender of the Faith." "DG Regina" also appears on Canadian coins.