They are generally.
What is a lamination error on a coin.
As a result the coin is struck more than once by the coin dies and this creates the multiple marks on the coin.
Split planchet errors occur on solid metal coins such as alloyed coins like bronze pennies or copper nickel five cent coins and occur due to impurities in those planchets.
Double or multiple strike errors happen when the coin fails to eject from the collar.
Lamination errors are planchet errors in which the surface of a coin cracks and flakes.
Split planchet errors are also similar to lamination errors which occur when parts of the coin flake off due to impurities or other abnormalities in the planchet.
The laminated part of the coin may be very small or run completely across the surface of the coin.
Lamination errors may be missing or attached to the coin s surface.
In the case of clad coins the outer layer may be completely or partially missing on one or both sides.
This doubled die will then strike out potentially hundreds even thousands of doubled die coins such is the case with the 1955 doubled die penny some coin analysts think 20 000 of these 1955 doubled die pennies were made.
This determines the size and shape of eventual coins.
It is generally believed that lamination errors are caused by contaminants in the alloy that cause the metal to separate along the horizontal plane.
While people used coins as currency for thousands of years the practice might have been closer to trading small bits of copper silver gold and other precious metals.
The die is imprinted by a machine called a hub.
Sometimes the laminated layer will fall away and be completely missing other times it can be folded back across the surface of the coin.
I can be as small as a pin head or almost as large as the coin itself and is easy to identify since it looks like metal leaf when attached and grainy if detached.
Lamination is when flakes of metal being to peel or flake of a planchet do to impurities in the alloy and this can be attached or detached.