"Since its introduction during the first Alien invasion, Elerium has proved to be an essential power source for interplanetary travel and military use. It is mined from distant planetary systems and transported back to Earth where its rarity ensures a high price. Tiny quantities contained in small pods fetch a high price. Corporations store pods in preference to gold because the stability of its value is guaranteed."
Note: exists in-game only as Elerium Pods and Elerium 115, but is just commonly called Elerium.
Elerium is only used as ammunition for plasma based craft weapons. Market quantities are generous. Stock quantities of elerium would only become scarce if many plasma weapons are used for craft combat. Elerium may become less useful since exotic vehicle weapons (no ammunition needed) are soon researched and are superior to any plasma craft weapons, hence, elerium becomes obsolete!
Elerium is found on the battlescape as Elerium Pods.
The monetary value of elerium is stable and is thus, a common item within every building within Mega-Primus, except Cult Of Sirius' Temples, when raiding. All elerium pods which have been acquired (picked up by an agent or recovered at successful completion of the raid) will immediately become 150 units of Elerium-115 at mission end. All pods are removed from an agent's inventory and placed within the cargo module using 8 capacity per pod.
When a pod is moved into base stores after landing, the Stores used is 150.