The first 5p coin in the UK would have been minted in 1967 (dated 1968).
This would give the Royal Mint time to distribute the coins to Banks for their initial release.
5p and 10p coins were issued in 1968 well in advance of "Decimalisation Day" in February 1971.
The reason for this was that the 5 and 10p coins were the decimal equivalents of the old Shilling and Florin and had almost exactly the same dimensions. These were the only two coins to survive the decimalisation process.
This was done to allow a period of acclimatisation before the full introduction of decimal curreny.
50p coins were first issued in 1969 replacing the Ten Shilling notes, again, for the same reasons.
5p
There was no 1977 British One Pound coin minted. The first general circulation One Pound coins was minted in 1983.
The George Washington dollar coin was the first of the Presidential dollar series. It was minted in 2007.
The first US Dollar coin was minted in 1794.
1.7mm
1952
The first US quarter was minted in 1796. It had a portrait of Miss Liberty on the coin.
minted
The United States first minted the large cent in 1793.
From 2011 yes
The first Eire Punt (One Pound) coin was minted in 1990, the last was minted in 2000.
1936