Coin, Indonesia, 2 Rupiah
1970 - AU(50-53) - Aluminum - KM:21
Stars flank date below denomination.
Rice and cotton stalks
2.3 gr
Aluminum
This common metal’s name comes from the Latin alumen meaning alum. Aluminum is a light metal with a bright and silvery appearance. Its use in its natural form is actually a recent development, as the procedure for extracting aluminum from bauxite was only perfected in the 19th century.
It is not frequently used for coins, with the exception of small denominations (centimes and other cents), because it is easier to find during periods of shortages or crisis. It is also used for tokens, emergency money, small coins, and certain medals.
A malleable medal, it has a great affinity towards oxygen and forms a protective layer of oxide on the surface when exposed to air.
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).
