Glossary of Terms
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

Karat

A unit of fineness representing 1/24th of the gold in a coin. 22 karat coins correspond to the .916 fine, 24 karats describes theoretically pure gold of 1000 fine, although this is generally expressed as .9999 fine.

Key Coin

The major or most important coin in a specific series. This is usually the most highly valued coin and/or the lowest mintage coin of that series.

Key Date

Generally descriptive of a coin which is considered to be one of the more difficult dates to obtain, either in any grade or in a specific grade, within a given series.

Kilogram

The major metric unit of weight representing 1,000 grams or 32.15 Troy ounces.

Knife Edge

Another term for wire edge.

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