abbreviation (e) // symbol
Esse is both the name for the in-character currency, as well as the name for the group currency earned through events and spent at the shop!
In the world, Esse is short for "Quintessential". It is a mint made of a gemstone inlaid in precious metal, which has absorbed both Fysa and Aria. The size of the gemstone (fleck < spark < bright), as well as the conductivity of the precious metal holding it (gold < copper < silver) denotes the value of the coin.
Esse can double as batteries in a pinch, to power plasts and other magical devices, which is where their value lies. They have to be charged in the silver lining, a space between Aria storms and Fysa storms, and it's one of the jobs of Storm Chasers. They can alternately be charged by having daemons carry the coins, but this takes longer and charges smaller amounts at once.
Esse's value can be viewed as equivalent to 1 USD in the world, when giving Esse values to things. The value of the coinage exactly is as follows:
Charging a coin doubles its value.