History of Money:

The invention of money took place before the beginning of written history. Consequently, any story of how money first developed is mostly based on conjecture and logical inference.

The significant evidence establishes many things were bartered in ancient markets that could be described as a medium of exchange. These included livestock and grain–things directly useful in themselves – but also merely attractive items such as cowrie shells or beads were exchanged for more useful commodities. However, such exchanges would be better described as barter, and the common bartering of a particular commodity (especially when the commodity items are not fungible) does not technically make that commodity "money" or a "commodity money" like the shekel – which was both a coin representing a specific weight of barley, and the weight of that sack of barley. 

Due to the complexities of ancient history (ancient civilizations developing at different paces and not keeping accurate records or having their records destroyed), and because the ancient origins of economic systems precede written history, it is impossible to trace the true origin of the invention of money and the transition from "barter systems" to the "monetary systems". 

Further, evidence in the histories supports the idea that money has taken two main forms divided into the broad categories of money of account (debits and credits on ledgers) and money of exchange (tangible media of exchange made from clay, leather, paper, bamboo, metal, etc.).

As "money of account" depends on the ability to record a count, the tally stick was a significant development. The oldest of these dates from the Aurignacian, about 30,000 years ago. The 20,000-year-old Ishango Bone – found near one of the sources of the Nile in the Democratic Republic of Congo – seems to use matched tally marks on the thigh bone of a baboon for correspondence counting.

 Accounting records – in the monetary system sense of the term accounting – dating back more than 7,000 years have been found in Mesopotamia, and documents from ancient Mesopotamia show lists of expenditures, and goods received and traded and the history of accounting evidences that money of account pre-dates the use of coinage by several thousand years.

 David Graeber proposes that money as a unit of account was invented when the unquantifiable obligation "I owe you one" transformed into the quantifiable notion of "I owe you one unit of something". In this view, money emerged first as money of account and only later took the form of money of exchange.

Regarding money of exchange, the use of representative money historically pre-dates the invention of coinage as well. In the ancient empires of Egypt, Babylon, India and China, the temples and palaces often had commodity warehouses which made use of clay tokens and other materials which served as evidence of a claim upon a portion of the goods stored in the warehouses. Because these tokens could be redeemed at the warehouse for the commodity they represented, they were able to be traded in the markets as if they were the commodity or given to workers as payment.

While not the oldest form of money of exchange, various metals (both common and precious metals) were also used in both barter systems and monetary systems and the historical use of metals provides some of the clearest illustration of how the barter systems gave birth to monetary systems. The Romans' use of bronze, while not among the more ancient examples, is well-documented, and it illustrates this transition clearly. First, the "aes rude" (rough bronze) was used. 

This was a heavy weight of unmeasured bronze used in what was probably a barter system—the barter-ability of the bronze was related exclusively to its usefulness in metalsmithing and it was bartered with the intent of being turned into tools. 

The next historical step was bronze in bars that had a 5-pound pre-measured weight (presumably to make barter easier and more fair), called "aes signatum" (signed bronze), which is where debate arises between if this is still the barter system or now a monetary system. Finally, there is a clear break from the use of bronze in barter into its undebatable use as money because of lighter measures of bronze not intended to be used as anything other than coinage for transactions. The aes grave (heavy bronze) (or As) is the start of the use of coins in Rome, but not the oldest known example of metal coinage.

Gold and silver have been the most common forms of money throughout history. In many languages, such as Spanish, French, Hebrew and Italian, the word for silver is still directly related to the word for money. Sometimes other metals were used. For instance, Ancient Sparta minted coins from iron to discourage its citizens from engaging in foreign trade. In the early 17th century Sweden lacked precious metals, and so produced "plate money": large slabs of copper 50 cm or more in length and width, stamped with indications of their value.

Gold coins began to be minted again in Europe in the 13th century. Frederick II is credited with having reintroduced gold coins during the Crusades. During the 14th century Europe changed from use of silver in currency to minting of gold. Vienna made this change in 1328.

Metal-based coins had the advantage of carrying their value within the coins themselves – on the other hand, they induced manipulations, such as the clipping of coins to remove some of the precious metal. A greater problem was the simultaneous co-existence of gold, silver and copper coins in Europe. 

The exchange rates between the metals varied with supply and demand. For instance the gold guinea coin began to rise against the silver crown in England in the 1670s and 1680s. Consequently, silver was exported from England in exchange for gold imports. 

The effect was worsened with Asian traders not sharing the European appreciation of gold altogether — gold left Asia and silver left Europe in quantities European observers like Isaac Newton, Master of the Royal Mint observed with unease.

Stability came when national banks guaranteed to change silver money into gold at a fixed rate; it did, however, not come easily. The Bank of England risked a national financial catastrophe in the 1730s when customers demanded their money be changed into gold in a moment of crisis. Eventually London's merchants saved the bank and the nation with financial guarantees.

Another step in the evolution of money was the change from a coin being a unit of weight to being a unit of value. A distinction could be made between its commodity value and its specie value. The difference in these values is seigniorage.