Industry WIKI

The đồng (chữ Nôm: 銅; chữ Hán: 元, nguyên) (; Vietnamese: [ɗôŋm]) was the currency of North Vietnam from 3 November 1946 to 2 May 1978. It was subdivided into 10 hào, each itself divided into 10 xu.

A piedfort (UK: , US: ; French: pied-fort or piéfort [pjefɔʁ]) is an unusually thick coin, often exactly twice the normal weight and thickness of other coins of the same diameter and pattern. Piedforts are not normally circulated, and are only struck for presentation purposes by mint officials (such as patterns), or for collectors, dignitaries and other VIPs. Piedfort is less commonly sp

The Standard Catalog of World Coins is a series of numismatic catalogs, commonly known as the Krause catalogs. They are published by Krause Publications, a division of Active Interest Media.

The Standard Catalog of World Paper Money was a well-known catalogue of banknotes that was published by Krause Publications in three volumes. These catalogues are commonly known in the numismatic trade as the Pick catalogues, as the numbering system was originally compiled by Albert Pick, but are also referred to as "Krause" or "SCWPM". Since the mid-1980s the titles have been owned by K

Toning on a coin is the change of colour brought about through oxidization, which forms a thin layer of tarnish on the metal's surface, typically as a result of interactions and chemical reactions with sulfur-containing compounds in the environment. Coin toning can vary in aesthetics, and thus can alternately add or detract from a coin's value. Coins with unusual toning colours or patter