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 New Zealand dollar to round the total price down (so that $4.99 became $4.95 instead of $5.00). Alternatively, many retailers rounded all their prices to the nearest 5 cents to avoid the issue entirely—so a New Zealand shopper often encountered products for sale at prices like $4.95. On 11 February 1991, $1 and $2 coins were introduced to replace the $1 and $2 notes in circulation. These coins were minted in aluminium bronze, and were the first New Zealand coins to be minted to metric specifications. At the same time, because the new $1 coin depicted a kiwi, the 20c coin reverse design