Niewmismatic Error Coins

METHODS OF COUNTERFEITING.

Making False Dies
The success of this method of course depends on the expertise of the counterfeiter. They engraved their dies by hand using traditional coining tools. They also can used a more sophisticated method, known as the "spark erosion technique". This process used a copper or silver counterfeit made from a cast of an original coin, to sink the die. Passing an electrical current between the counterfeit and the steel used for the die results in the former cutting into the steel to leave it's impression. As it is very difficult to distinguish between genuine coins and fakes struck from false dies manufactured by the "spark erosion technique", I make no apologies for not being more explicit regarding this method.

Using Genuine Dies
Perhaps this method cannot be said to result in counterfeit coins. Nevertheless, a German mint-master was convicted of this offence in 1975.

Alteration of a Genuine
This means that a common type of coin is altered in an attempt to pass it off as an extremely rare piece. This might involve, for instance, changing the date of the common 1982 to 1972 and 1981 to read 1971 - a key date rarity in the Malaysia Parliament 10 cents coin series. Such forgeries can always be detected without too much difficulty.
Casting
This is the cheapest and commonest way of making forgeries. There are two methods of manufacturing items by this means. The first is when molten metal is poured into mould made from the impression of a genuine coin. The resultant forgery is easily detected as such because the whole effect is "fuzzy", i.e. the edges of the design are blunt and blurred. Furthermore, air bubbles are rife on the surface of the piece.
The second and subtler method, said to have been discovered by an Egyptian dentist, is know as pressure casting. Here the mould is placed between the two poles of an electromagnet to draw the metal back into the recesses of the mould of force out the air bubbles. The result of this method are much more difficult to detect. However, the diameter of a forgery produred by the casting method is always less than that of a genuine original.

Electrotyping
This process of making a replica of a coin is somewhat similar to silver - plating. The process given a faithful copy but there is a slight variation both in size an weight. Because the obverse and reverse are made separately, one is able to detect the join of the two halves on the edge. Naturally, this joint can be plated or otherwise disguised.