Answer:
The 1827 British Halfpenny is made from copper, weighs 9.337 grams and is 28 mm in diameter.
There were 5,376,000 minted.
They have a left facing King George IV (laureate Head) on the obverse and the seated figure of a helmeted and robed, shield and trident carrying Britannia on the reverse.
The date is in the exergue below Britannia.