The Sovereign is still legal tender, but since the value of a gold Sovereign far out weighs its face value of One Pound, only a fool would spend one for a Pounds worth of goods. Sovereigns (or any British gold coin) only cease to be legal tender when through wear, they fall below a certain weight.
The only reference I can find to a British 1977 coin set, is for a set of 7 coins commemorating the Silver Jubilee of Queen Elizabeth II. A British 1977 set of Proof coins (Silver Jubilee Commemorative - Proof Crown plus 50p to halfpenny inclusive) could fetch up to £12 GBP. It should be noted that the value of any "coin set" is dependant on it being in its original packaging and condition. A reputable coin dealer will be able to give a more accurate valuation.
A British 1977 cupro-nickel Crown (25 Pence)(Elizabeth II)(Silver Jubilee Commemorative), uncirculated and in absolute mint condition could fetch up to £1.50 GBP. A British 1977 cupro-nickel Crown (25 Pence)(Elizabeth II)(Silver Jubilee Commemorative)(Specimen in presentation folder), could fetch up to £2 GBP. A British 1977 cupro-nickel Crown (25 Pence)(Elizabeth II)(Silver Jubilee Commemorative)(Proof FDC), could fetch up to £5 GBP. A British 1977 Crown (25 Pence)(Elizabeth II)(Silver Jubilee Commemorative)(Silver Proof in case FDC), could fetch up to £22 GBP. The values quoted are the best possible for the best specimens in their grades, but may be significantly lower due to varying demand for the coin and the prevailing economic climate. A reputable coin dealer will be able to give a more accurate valuation based on inspection of the coin. NOTE - The 25 Pence coin was known as a Crown from its first issue in 1972 until 1990 when the Five Pound coin, being of similar size, became known as the Crown and the 25 Pence coin was discontinued.
Tender Forever was born in 1977.
Tender Huang was born on February 19, 1977, in Taiwan.
Crown Books was created in 1977.
Seattle Slew won the Triple Crown in 1977.
Prince Charles, the Prince of Wales, has only appeared on two British coins to date. 1. The 1981 25 Pence (Crown) coin commemorating his marriage to Lady Diana Spencer. 2. The 1998 Five Pound (Crown) coin commemorating his 50th Birthday. The 1977 coin to which you possibly refer is the Silver Jubilee of Queen Elizabeth II commemorative 25 Pence (Crown) coin.
Seattle Slew
If by "new" you mean a decimal coin, the Half New Penny and Half Penny coin was in circulation from 1971 to 1983. The 25 Pence (Crown) coin was only issued in 1972, 1977, 1980 and 1981 and was intended to be a commemorative rather than a circulation coin. The Five Pound Crown replaced the niche of the 25 Pence Crown in 1990. The uni-metallic Two Pound coin was issued in 1986, 1989, 1994, 1995 and 1996 and was intended to be a commemorative rather than a circulation coin. The general circulation bimetallic Two Pound coin was first issued in 1997.
Made in 1977 it is worth $695.00 at 100% condition.
1977-he is my favorite Triple Crown winner Secretariat won it 4 years previous and Affirmed won the next year