Most of the civilized world use an equivalent coinage based monetary system. That means they all use a common system of currency based on amounts of different precious metals, all of the same mass: one dram = 4 grams. Thus 100 gold pieces (or silver or copper) would be 400 g, or just about 14 oz. Each minting authority (usually the hierophant of one of the more civilized hierarchies) would use their own designs. A minting authority would use an identical design, including an inscription denoting date and source, for the obverse of the various coins (except platinum, see below) with thematic similarities from authority to authority for the reverse.
All coins are milled circular disks with the same diameter, 2 cm (about 10% larger than the US dime). Since the mass is fixed, higher density coins, i.e. Gold and platinum, are roughly half the thickness of copper and silver.
Eldarhaven does not have its own coinage. Until recently commerce there and for quite some distance was carried out predominately with specie minted in Plii before the Darkness. The obverse of Plii coinage is a filled ray octagon, with lettering in dwarven runes around the border. Most coins have “21AF:PAN OUAS EXOUS:RK HIER TEM:” or “EPX PAN ANTH:RK PROT MET I:”. Since they are at least 88 years old, they are starting to show a bit of wear, though fortunately except maybe for the copper they don’t see a lot of day to day handling.
In the continuing recovery from the Darkness, a few hierarchies are again minting fresh specie. In just the last few years increasing commerce with the interior and overseas has introduced a number of “exotic” coinages in Eldarhaven, the most prominent being from Avilla, with an obverse consisting of a familiar seven star formation, “Lis’s Net”.
The foundation of the currency system is the one dram gold coin, the aurum, abbreviated
Ar, though this name was rarely used in common speech, instead replaced with a local colloquialism. In Eldarhaven, it is called an orb, derived from the symbol on the reverse of the gold coin struck in Plii. (This name is used in Eldarhaven for all gold coins, no matter the source.)
The day to day business of the middle and even the upper classes is usually conducted in silver, not gold. (The average peasant in the countryside might go years between seeing, let alone holding, a gold piece.) The silver penny is set by fiat to be 1 p =
Ar 0.1. The reverse of the penny in Plii is a standing robed female, face on, with a drawn sword. In general a penny usually has a throne, crown, mace, faces, or other symbol of authority.
For prices and transactions the plural of penny is pence (abbreviated pp), but for collections of the coin the plural is pennies: “That bow is yours for five pence, sir.” “Here my good man, I have five silver pennies for you.”
The most common coin in the purse of the hoi poloi would be the copper cent, worth 1 ¢ = 0.1 p =
Ar 0.01. Sometimes, if smaller values are needed for a transaction, the cent can be physically cut into pieces: one cent can yield two hacents or four farthings. The reverse of the Plii cent is a sheaf of grain, more generally an agricultural symbol, superimposed with a quartering cross.
The platinum coin is
PP 1 = Ar 20, and is usually referred to just as a “platinum piece”. It is used most often as a more compact accounting medium, to be found only in vaults and strong boxes, and is rarely carried on the person of even the richest men. The obverse of the platinum piece is unusual, a profile portrait of the mint’s current hierophant, and the letters “PP” on the reverse. There are of course other metals, gems, and rare materials of even more value, but they have no fixed exchange rate.
What they look and feel like, some (out of game) historical comparisons
Each individual coin will weigh a bit less than twice that of the US dime. That bulging purse probably has thirty or forty coins weighing 150 g or 5 oz (a third of a pound). The arum has a thickness of 0.7 mm, a bit more than half of a dime’s thickness. These are not big weighty hunks of gold, and there isn’t a lot of room for the minters art. Still, for comparison, the 19th century british “sovereign” is only twice as heavy, and supposedly was worth a pound ‘sterling’ (which at the time actually was the value of almost three and half pounds of actual silver). The american “gold dollar” was of comparable size as the aurum. For a more medieval era, the Eldarhaven penny weighs almost three times the Anglo Saxon silver penny (240 of which became the pound). Later, Henry IV (who took over the throne admist almost complete economic collapse) dropped the English penny to only a gram, a quarter of the Eldarhaven penny. If you want a big coin, you would have to look for the silver two shilling piece, which in economic terms would have a value equal, roughly, to that of the aurum/orb, and hence almost a fortune for your typical inhabitant. And those big hunks of gold that the pirates are throwing about are probably spanish 4 doubloon pieces, but still not much more than twice the size of the aurum.
When coming across treasure troves, it might be helpful to know that it takes 250 coins to reach a kg (or about 110 to the US pound), taking up a volume of only about a quarter cup (US) for gold, twice that for the more common coinage. So an individual might manage packing out a couple thousand or so without thinking about returning to hire that pack mule, or having to leave their soon to be replaced armor behind. She wouldn’t even need very many, or very big, bags, as long as any stitching was sound..