
The 2004 two pounds piece commemorates the 200th anniversary of Trevithick's Locomotive for the railway. Only 1,500 gold proof 'Steam Locomotive' two pounds pieces were issued by the Royal Mint in 2004.
Richard Trevithick (1771–1833) was a British inventor and mining engineer from Cornwall. He was an early pioneer of steam-powered road and rail transport and developed of the first high-pressure steam engine. He built the first full-scale working railway steam locomotive in 1804 and Trevithick's unnamed steam locomotive hauled a train along the tramway of the Penydarren Ironworks, in Merthyr Tydfil, Wales.

Designed by Robert Lowe, the reverse depicts Trevithick's Locomotive and the denomination 'TWO POUNDS' surrounded by a cog representing the Industrial Revolution, and the inscription 'R. TREVITHICK 1804 INVENTION INDUSTRY PROGRESS 2004'.
Queen Elizabeth II's fourth portrait can be seen on the obverse, designed by Ian Rank-Broadley.

The two pounds piece is made of solid 22 carat gold (Gold Fineness of 0.916), and weighs 15.98 grams. It has a diameter of 28.40mm.
The outer disc is made of 'red' gold, with the inner disc being 'yellow' gold.
The coin is housed in its original Royal Mint acrylic screw top capsule, presented in its Royal Mint green leatherette case, accompanied with an individually numbered certificate of authenticity (COA).