Little Help With Some Terms

Thanks for the answer, JimmyJames. Here in Brazil we use to do a lot of "coin roll hunting". That's because the monetary pattern changed a lot through the years. The newest circulating money is "Real" and it started in 1994.

Thanks Sap for your answer!

"Dye" is not a coin-related term - it means coloured pigments used to impart colour onto fabric. The cylindrical metallic objects used to strike coins are called "dies".

"Die doubling" is an effect seen on some error/variety coins. A working coin die is made in a similar way to how a coin itself is made, only backwards, by pressing the blank die, a soft steel cylinder, into a hardened steel "hub" which replicates the coin design. This hub is pressed into the blank die several times, and if it becomes misaligned or rotates slightly during this process, the design can be duplicated, or "doubled". The 1955 cent is perhaps the most famous and spectacular example of a doubled die coin variety in the American series.

A similar though less spectacular effect can be caused when a perfectly ordinary die chatters or vibrates as it strikes a coin; this is known as " Machine Doubling" and is not considered a significant error or variety.

The correct terminology is "doubled die" or "die doubling". "Double die" is lazy talk; error and variety experts sometimes get upset when they see people use it or say it, since it is technically incorrect.