About the Design:

Obverse
Penthesilea, Queen of the Amazons
Four dolphins

Lettering:
MALTA
1977

Engraver: Christopher Ironside 

Reverse
Value within wreath

Lettering:
2
CENTS

Proof Coins
The term "proof" refers to the coin's finish. The Mint recognizes a proof coin as “a specially made coin distinguished by sharpness of detail, usually with a brilliant mirror-like surface.” Proof coins are struck at least twice and treated with special dies which make their features more defined, detailed, and glossy.

Composition    Copper-nickel
Weight           2.25 g
Diameter    17.7 mm
Thickness    1.1 mm
Shape            Round