Kathron Coins
The standard for coin sizes across Arthea is known as the Kathron coin standard, named after The Kathron Delve, the dwarfish city where the standard was developed. The standard for coins helped trade expand after The Great Disaster, and had a significant impact on the speed at which the free people re-established their communities.
The standard defines the size and weight of a coin and the purity of its metal, the value of such coins is determined by local factors. Under the standard the intention was to establish a common size for coins, with slight variation of thickness to keep the weight and relative value of the metals in proportion. The standard also states that the outside of silver and higher value coins should carry milling to prevent unscrupulous halflings filing the edges.
The standard does not specify which images should be displayed on each face of the coin, although it is customary to see the monarchs image on one side and some image of importance to the region where the coin was minted on the other side.