Coin, Estonia, 10 Senti
2002 - AU(50-53) - Copper-nickel Aluminium - KM:22
1.89 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(50-53)” 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(50-53)
This means – more prosaically – that the coin has circulated well from hand to hand and pocket to pocket but the impact on its wear remains limited: the coins displays sharp detailing and little sign of being circulated. The number (50-53) indicates that at least half of the original luster remains. Closer examination with the naked eye reveals minor scratches or nicks.
You might be wondering why there are different ranges of numbers behind the same abbreviation. Well, we’ll explain:
The numbers are subdivisions within a category, showing that the state of conversation is the same but coins may be at the higher or lower end of the scale. In the case of AU, the range (55-58) indicates that the luster is better preserved in than a similar coin described as (50-53).
