Volantic stone

A type of rock native to Volanil, and only quarried from Molsten and surrounding areas atop Volan Peak (the geographical location, not the political state). The buildings in the city of Molsten are made entirely of Volantic stone, but quarrying those buildings is both very difficult and very illegal.

Typically sold as chunks of rock and then refined into jewelry or other polished shapes, Volantic rock is sought after by mages (and by traders hoping to ship it to mages) because of its unique magical properties. The material has an absorptive nature; a chunk of Volantic rock that has occupied a space near a strong source or siphon of magic begins to take on the nature of that magic.

Within that scope, however, the magical effects of "charged" Volantic rock can still be unreliable. Exactly what manifests and when has proven elusive to accurately predict.

However, it can mold and change with time, depending upon its proximal magic. For instance, a Volantic stone necklace worn by an elemental mage for fifty years might imbue resistance for those elemental types of damage, but if it's passed onto a necromancer for another fifty years, it might evolve into a channel stone for elemental soul magic such as summoning and controlling elemental beings.