The Union of Soviet Socialist Republic issued large (32 mm diameter) 1 rouble coins in many different patterns between 1965 and 1991. All these coins have the same reverse side, with large CCCP letters, a large 1 numeral, the Russian word for rouble (which looks something like PYbAb) and a circular shield with grain, globe, hammer, and sickle.
All these coins are minted in copper nickel, so their value is low. The dates are on the edge of the coin. You can use this spiffy date converter to find the date of your coin. Some coins were issued in proof form, as well as normal coins. Proof coins are special, extra-nice coins made solely for collectors.
Regardless of date or proof, these coins all catalog approximately as follows:
worn: $1 US dollar approximate catalog value
average circulated: $5
well preserved: $10
fully uncirculated: $20
coins dated 1964 and 1991M are common and catalog at $2 average circulated, $9 fully uncirculated
There are some *better dates* as listed below. Values are for coins in average circulated condition:
1966: $10 average circulated
1967 with 1966 on edge: extremely rare
1976 with 1975 on edge: $100
1979, 1980, 1981, 1982, 1983: $12
1988 with 1989 on edge: $100
1990 with 1989 on edge: $100
There are other modern CCCP coins, minted in larger denominations like 3 roubles, 5 roubles, 10 roubles which are made of precious metals such as silver, gold, and palladium. These are worth their weight in precious metal.