Etherium

From MTG Salvation Wiki

Etherium is a magical æther-infused alloy found on Esper. According to the myth, it was created by the sphinx Crucius, and since then most of Esper's inhabitants have parts of their body replaced by etherium. The stocks of etherium are measured in rods. Ultimately the Ethersworn are planning to fuse every living being with this metal.

It is unknown how Crucius made the alloy, even Sharuum could only show how to thin existing etherium. The Seekers of Carmot believe, that one ingredient is a substance named carmot and they possess the Codex Etherium, which supposedly reveals the location of carmot. However it was revealed by Tezzeret that it was a fraud, so the creation of etherium is still unknown.

Notable items made of etherium are the Filigree Texts and Tezzeret's Infinity Globes.

[edit] Trivia

Carmot was also thought to be a component of the Philosopher's Stone.

Alara block
Expansions: Shards of Alara | Conflux | Alara Reborn
Alara storyline
Shards: Bant | Esper | Grixis | Jund | Naya
Characters: Ajani | Elspeth Tirel | Nicol Bolas | Sarkhan Vol | Tezzeret
Others: Etherium | Kathari | Leotau