Monaco, Rainier III, 10 Francs
1982 - PR - Copper-Nickel-Aluminum - KM:154
10 gr.
Cupronickel aluminum
Cupronickel (or copper-nickel) aluminum is an alloy comprising (as you may have guessed) copper, nickel, and aluminum. These days, cupronickel is extremely popular and a firm favorite for use in coins. From time to time, small quantities of third metals such as zinc, tin, and, in this case, aluminum are added, which help to boost its great resistance to mechanical wear even further.
The addition of aluminum to copper and nickel gives coins an appealing golden shine, easily recognizable, for example, in certain French centimes engraved by Lagriffoul in the 20th century, but also in trial coins. Depending on the proportions, the hue may also tend towards silver with golden yellow highlights.
The alloy is also very de rigueur for tourist tokens in France.
An “AU(55-58)” quality
As in numismatics, it is important that the state of conservation of an item be carefully evaluated before it is offered to a discerning collector with a keen eye.
This initially obscure acronym comprising two words describing the state of conservation is explained clearly here:
About Uncirculated(55-58)
This means – more prosaically – that the coin has been in circulation but sufficiently little that its original beauty is preserved almost in its entirety. The wear is barely visible and any other defect can only be identified with a magnifying glass or a particularly keen eye. The number (55-58) indicates that between three quarters and almost all of the original luster remains.
