Currency

Prior to The Fall of Civilization
Prior the The Fall, Aloria would use the standard D&D currency. Except for the Electrum. That doesn't exist in Aloria.
After The Fall of Civilization
After The Fall and before the Steam Era, gold, silver, and platinum along with other precious metals became a far more valuable resource and far more hard to find. As such, using it in standard trade wouldn't be cost effective, nor would the average player have access to it without risking being robbed.
Although bartering is far more likely after The Fall, when a economy is used, people tend to consider these basic metal coins as good currency:

Material	Description	Value	Rarity
Aluminum	A silvery-white, soft, non-magnetic and ductile metal.	Basic coin.	Abundant
Tin	A soft, silvery white metal with a bluish tinge.	Worth 10 aluminum.	Common
Copper	The metal solidifies with a dull gray color.	Worth 10 tin.	Uncommon.
Silver	A soft, ductile, malleable, lustrous metal.	Worth 10 copper.	Rare.
Gold	A soft, yellow metal.	Worth 10 silver.	Extremely rare.
Platinum	A dense, malleable, precious, silverish-white metal.	Worth 10 gold.	Legendary.

Steam Era
To be decided.