It is really easy, the Royal Mint did not produce any 1852 British Pennies.
British Pennies minted from 1825 to early 1860 were 34mm in diameter.
British Halfpennies minted from 1825 to early 1860 were 28mm in diameter.
An Australian Penny or Halfpenny with a "Y." (PENNY.) mintmark indicates that the coin was minted at the Perth Mint. An Australian Penny or Halfpenny with a "I" mintmark indicates that the coin was minted at either the Calcutta or Bombay Mints in India.
I think by "hay penny", you possibly mean Halfpenny. The Halfpenny was one of the lowest denominations of the British currency and they were never struck in gold. Depending on when they were minted, they would have been struck in copper or bronze.
In 1066, the Halfpenny was an improvised coin. It was a Penny, literally cut in half. The symbol for the British Penny has long been a lower case "d" for the Roman "denarius" which was a Roman coin predating the Penny. In all probability, 1 Penny was shown as "1d" and 1 Halfpenny as "½d".
An Australian 1942 Halfpenny minted in Melbourne, has no mintmark. An Australian 1942 Halfpenny minted in Perth has a dot (.) after the (Y) in PENNY (PENNY.). An Australian 1942 Halfpenny minted in Bombay has an (I) below the King's head.
The British predecimal Halfpenny, Penny, Threepence and Sixpence did not have an equivalent coin in decimal currency.
As far as general circulation coins are concerned, easily the most valuable Australian Penny is the 1930 Penny and the most valuable Halfpenny would be the 1923 Halfpenny.
The coin is either a Penny or a Halfpenny. A British 1963 Penny or Halfpenny, uncirculated and in absolute mint condition could fetch up to £1 GBP. If it has been circulated but still in good condition, not much. A reputable coin dealer will be able to give a more accurate valuation.
The British Halfpenny was first produced about 1300 AD to replace the custom of cutting Penny coins in half to achieve the required value. Many countries of the British Empire/Commonwealth also produced a Halfpenny coin for their respective currencies. Most of those countries including Australia, Britain, New Zealand and South Africa, to mention a few, produced a Halfpenny coin in 1942. The US has never minted half penny coins. The US made half cents from 1793 to 1857.
The first New Zealand Penny and Halfpenny was issued in 1940.
There is no difference between penny stocks and cent stocks.
British coins minted in 1775 included the Guinea, Half-Guinea, Halfpenny and the Farthing. British coins in circulation in 1775 included the Five Guinea, Guinea, Half-Guinea, Shilling, Fourpence (Groat), Threepence, Twopence, Penny, Halfpenny and the Farthing. ,
The British "Cartwheel Penny" and "Cartwheel TwoPence" were only issued in 1797. The Isle of Man "Cartwheel Penny" and "Cartwheel Halfpenny" were issued in 1798 and 1813. Any of these coins in excellent condition could be considered valuable.