The first English gold coin was minted in London in 1257 for King Henry III; a fact only known from research in the early 18th century. It had a value at the time of 20d, although it is always referred to as a 'golden penny'. Some believed in the past that it was not issued with the intention of it circulating as currency, but rather it was expected to be used in the giving of alms (ie for charitable giving). This may, however, be a Victorian assumption, because there is evidence that the merchants of London petitioned Henry III to withdraw it. The king half complied with the request and said no one was compelled to receive it in payment and if they did so they could exchange it at The Mint for the equivalent value in silver pennies, less a halfpenny admin charge! The coin was soon completely withdrawn, however, when in 1265 its bullion value rose to 24d. People began melting them down, as did the Crown when they were officially withdrawn. It is thought 52,000 were originally issued, but how many survived the meltdown is unknown. Sir John Evans, as long ago as 1900, suggested the story of almsgiving arose from the king giving the Church a number of the coins at the time of their withdrawal so as they could be melted down and the gold bullion used by the Church for charitable purposes.
Few examples remain today, and only eight are known with any certainty. The first acquired by The British Museum cost the the grand sum of £41.10/-. What it is worth today, if one was to come onto the market is anyone's guess; but certainly, I believe, you would have to attend the auction with more than half a million pounds in your pocket.
There was then a gap of 90 years before the Royal Mint tried the experiment once more. In 1344 Edward III issued three gold coins - the Leopard, half leopard, and quarter leopard worth 6/-, 3/-, and 1/6d respectively. There wasn't really a demand for high value coins before the mid 14th century, but the more pertinent reason may be because the availability of gold was extremely limited, not only in England but right across Europe. Attempts to find gold in England focussed on Devon and Cornwall but there is little evidence that other than miniscule amounts none was found. In 1324/25, for example, the London goldsmith, John de Wyrlingworth, was charged by the Crown with finding gold in Devon. He gave up after a month having found less than the cost of his own expenses ! The only large-ish goldmines were in Mid and North Wales, the most famous at Dolaucothi, but these could still only contribute small amounts to the Mint.
From Edward III right through the Middle Ages (ie until the reign of Richard III ended on Bosworth Field in 1485), gold coins continued to be produced, although their names changed from divisions of a leopard to divisions of a noble. In 1470 Henry VI added an angel (6/8d) and half angel (3/4d) to the coinage. Edward IV replaced the noble with a rose ryal (10/-).
So, if we couldn't mine gold here where did it come from? The answer is from melting down earlier gold coins, and using less gold in the making. Well, yes, but that isn't an answer. Where did the original gold come from? From international trade in wool, and later cloth, with Northern Europe. By 1396/98, 57% of the Royal Mint's gold came from taxes on the wool trade.
OK, but.....where did the European traders get the gold? Partly from European goldmines in the East, such as from Kremnice in Hungary. But there was never enough to satisfy the market. Other gold came from trading with the Islamic Middle East who used gold coinage throughout the Middle Ages, as well as from trade with Christian Byzantium, with its gold solidi.
As an aside, Henry III employed his goldsmith, Edward Fitz Otto, to source the gold for his own coins. Fitz Otto in turn obtained the gold from another London merchant, Solomon le Evesque, a Jewish businessman, who acted as a middleman - maybe, I guess, with contacts in Islamic Spain?
There was an almost equal problem with silver which was only finally solved with the opening up of silver mines by the Spanish in The New World. But the supply of gold throughout the Middle Ages was always less from European mines than was silver, as there were substantial silver mines opened up in what is now the Czech Republic in the middle of the period.
In other words there was still a shortfall in gold to be covered. The answer is that it was made up by West African gold. The great example is that of the Empire of Mali in the 14th century, although African gold was being used to mint gold coins in Sicily and Christian parts of Spain as early as the end of the 12th century. Under its great leader, Mansa Musa (reigned c.1312- c.1337), said to be the richest man that ever lived, the Malian Empire supplied fifty per cent of all the world's gold at this period. It reached Europe through trade, and principally trade from Islamic Morocco to Islamic Southern Spain, and trade with the great medieval cities of Italy - Genoa, Florence, and Venice. These Italian cities began minting gold coins themselves in the middle of the 13th century. Finally, some of it made its way by trade to England. By the reign of Edward IV (1461-70 and 1471-83), however, English merchant ships had reached the West Africa coast ('The Gold Coast') and had begun to trade for African gold direct. The world was opening up by the end of the 15th century, and when the Spanish reached South and Central America large amounts of gold arrived in Europe along with silver, and the story of medieval gold supply ends.