These are large (37 mm) coins issued by Gibraltar between 1967 and 1970. They are made of copper-nickel. Typical values:
worn: less than $1 US dollar approximate catalog value
average circulated: $1
well preserved: $3
fully uncirculated: $8
Proof versions of this coin are made especially for collectors and are usually found in special packaging. Proofs contain 0.455 troy ounces of silver, and are worth their weight in silver. At the current price, that's about $15. But the price of silver changes every day. Look it up.