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 Indian rupee of fraction of a rupee. In June 1964, the term 'Naya' was dropped and the coins were reminted. The legend in Devanagari script explaining the value of coin in terms of fraction of a Rupee continued till it was finally dropped from the new design minted 1964 onwards. The coin minted from 1965 did not have the legend in Devanagari, explaining the value of the coin as a fraction of the rupee. Small denomination coins which were made of bronze, nickel-brass, cupro-nickel, and aluminium-bronze were gradually minted in aluminium.The first coin minted in such type was the 3 Paisa coin