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 rupee, 1/4 rupee, 2 anna, 1 anna, 1/2 anna & 1 pice coins, and are referred to as the anna series or pre-decimal coinage. Under the anna series, one rupee was divided into 16 annas or 64 pice, with each anna equal to 4 pice. In 1957, India shifted to the decimal system, though for a short period of time, both decimal and non-decimal coins were in circulation. To distinguish between the two pice coins in circulation, the coins minted between 1957 and 1964 were printed with the legend “Naya Paisa” (“New Paisa”). The denominations in circulation were 1, 2,