Fio'tak

Fio'tak is a hard, ultra-dense, nano-crystalline metal alloy developed and used by the Earth Caste of the Tau Empire for use in a variety of applications; most commonly as armour. Fio'tak is very resilient to penetration due to its impact-resistant structure, and is lightweight compared to more conventional Imperial materials such as plasteel. When it comes to deflecting and withstanding damage, Fio'tak is comparable to the ceramite used in the Imperium's Space Marines’ Power Armour, but weighs substantially less.

Fio'tak alloy variants are used by the Tau in a variety of applications, including in infantry armour such as Combat Armour and Recon Armour, Tau skimmer and aircraft vehicle armour, Tau Drones, Tau buildings, and Tau Battlesuit armour. Battlesuit Fio'tak armour is shaped to help deflect solid shot, and also has a liquid metal coating that reflects medium grade laser fire. In some cases, such as the XV88 Broadside Battlesuit or XVI 04 Riptide Battlesuits, additional nano-layers are added to upgrade the armour's thickness so that is protection capabilities are comparable to Tactical Dreadnought Armour. The construction techniques of Fio'tak are unknown to the Imperium as the Adeptus Mechanicus is forbidden from investigating dangerous alien technology by the Ordo Xenos.