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 its controversial design resembling a cross, it was criticised and was not minted in large numbers. Another reason for its availability being scarce is that it was minted only in one (Noida) of four mints in India. Coin dealers and the public who got this coin hoarded it and it never came into circulation. It is available for sale on some auction websites, but the price of this coin is very high in comparison to its denomination due to the uncertain number of issued coins. Some coin sellers claim that this coin is a limited edition. However, official information is