World of Astra
Ethrum is a volatile, elemental substance, found in crystal or rarely liquid form. There are known to be seven known varieties, roughly analogous to the six Winds of Ether, with an additional clear variety sometimes found. Ethrum is found in different areas of the world, and not always matching the Ether mix in the area. The Kalth area is known for it’s large quantities of Verdant and Crimson Ethrum, while the Ravanas estates in southern Astra is known for it’s high quality Pale and Black Ethrum.
A useful material known for it’s large stores of power, it is utilized in many projects, and is something of a requirement for modern day to day life. Ethrum can be used for many things, from spells and magical ingredients, to power sources in alchemical constructs. It can be used in solid crystal forms, ground into a powder, burned into a vapor, or even sometimes drunken in liquid forms in potions. Each of the seven variates are useful for different projects, but the materiel as a whole is traded in nearly every part of the continent.
When traded as a raw substance, ethrum is traded by the pound, with one pound of any of the seven varieties normally trading for 100 gold. Normally, traders will treat any variety as the same for market purposes, though persons looking for a specific effect will tend to pay more for the specific kind they are looking for. Also, the price with sometimes fluctuate with the ethrum state, with powdered ethrum selling for sometimes up to 30 percent less then the solid cystal types, to pure liquid, which can fetch up to 50 percent more in certain markets.