Lava is used by the mer the same way that humans used electricity. They are dependant on lava for heating, such as cooking and its uses in crafting and lighting.
Uses[]
Lava is piped through many mer buildings and settlements. Or they can be filled in glass globes. Since lava cannot be piped into an iceberg, Ondalinians imported lava globes. Lava is also used for cooking, such as when Astrid and Becca remember Månenkager, a cake made of pressed krill, baked in lava ovens and there is a lava stove in Fossegrim and Coco's hideout. Although waterfire can be used for lighting and heating as well, it is only when mer are out in the wild and that method is comparable to modern humans using airfire for such things- just antiquated.
Process of mining and refinement[]
Magma is first found through a lava seam deep in the crust of the sea floor. A bubbler- a type of tool, a flexible tube- is used by the goblins- usually the Feuerkumpel tribe- to see what type of magma is below and potentially what type of lava it could be used for. There are many grades and varieties. Glimrende is the finest, however it is only good for lighting. Sterkur is much stronger and is thus used for heating.
The Magma is then channelled or mined. It is taken to refinements, to be turned into lava- the white lava is used for lighting. This type of lava can either be piped and/or poured into globes of glass strong enough to withstand its lethal heat, crafted by the Höllebläser Kobold tribe.