There are disputes about where did the first coin money occur. What is known for sure is that minted money started to be used as a universal item of exchange in the period of the 7th or 5th century B.C.
Sayings of Herodotus
By Herodotus, who is considered to be the father of history, the first appearances of money forged out of gold and silver were in the kingdom of Lydia(modern Turkey) some-time in the 5th century B.C. Despite the irregular shape, the minting of coins implied a strict weight system of 14.1 grams. Severe punishments for forgeries were present and executed without an exception. Later researches established that their mixture was from electrum – a natural mix of gold and silver extracted from the earth. In most of the transactions, coins were weighed rather than counted.
On the other hand, Aristotle is saying that the first creation of coins through minting was committed by Phrygia. Numismatists think that the first coins were minted on the greek island of Aegina.
Whatever the truth was, the fact that remains is that people created an item used for expressing the value of all other merchandise exceeding over the obstacles of bartering. But the coins weren’t the first items used as money. It was the promissory notes.