In
1963 small coins began to vanish from circulation at an alarming rate. The mint blamed this on coin collectors, and began a series of changes that violated common sense.
Like they had done in
1942 they looked for replacements for silver in
dimes and
quarters. After much searching they decided to change the composition to a clad a sandwich made of copper and cupro-nickel (a
copper nickel alloy). They deleted all
mintmarks from US
coins made between 1964-1967. All of which caused hoarding of pre-
1964 coins
The real cause of the shortage was the fact most coins spent 28 to 30 days each month in vending machines, parking meters, and phone booths. A fact documented by noted author
Walter Breen at the time.
This is another example of the love hate relationship the mint has had with collectors (see
coins you cannot legally own)