The tectonic mask lasts for 100,000 charges of combat before degrading to nothing; it cannot be repaired after degrading to 0 charges. The mask, if dyed, can be recharged with tectonic energy; each tectonic energy provides 1/14 recharge (~8,334 charges). Once equipped, it instantly becomes untradeable, even if it has not been used in combat.
Losing the tectonic mask by being killed in the Wilderness will result in a fraction of the original tectonic energy being dropped on death, based on how degraded it was, rounded down. For example, if the mask had 52% of its charges remaining, 7 tectonic energy would be dropped on death. This can be used to refund most of the cost of the mask, although the stones of binding are not returned.