Metallurgical assay and the U.S. Mint continue to produce precious metal bullion coins for collectors and investors. The precious metal purity and content of these coins is guaranteed by the respective mint or government, and, therefore, the assay of the raw materials and finished coins is an important quality control. In the UK, the Trial of the Pyx is a ceremonial procedure for ensuring that newly minted coins conform to required standards. Metallurgical assay A metallurgical assay is a compositional analysis of an ore, metal, or alloy. Some assay methods are suitable for raw materials; others are more appropriate for finished goods.
Coins of the Canadian dollar to the $1 and $2 coins as well. The 50¢ piece is regularly minted, but not in large quantities; it is very rare to come across this coin in circulation, although an unsuccessful attempt was made by the Mint to promote the use of the coin when a special edition was released in 2002 marking the 50th anniversary of Elizabeth II ascending the throne. Coins issued in 2002 do not have the usual mint date, which normally appears on the reverse side. Instead, the 2002 coins have a commemorative double-date on the obverse side: "1952-2002", to commemorate the 50th anniversary