Mark of Sanctification

A Mark of Sanctification is a token used to upgrade tier 10 Icecrown Citadel gear.

Six versions exist: Three normal and three heroic. Normal versions of the Mark upgrade from the base tier 10 gear, while heroic versions upgrade further to the heroic tier 10 gear. Like other gear tokens, there are three types:

Source
Marks of Sanctification (all sorts) drop from the last boss of each wing of Icecrown Citadel: The non-heroic Marks of Sanctification are only found when raiding as 10-man Heroic or 25-man Normal. The heroic Marks are only found when raiding as 25-man Heroic. Marks are not found under 10-man Normal.
 * Deathbringer Saurfang (via Deathbringer's Cache)
 * Professor Putricide
 * Blood-Queen Lana'thel
 * Sindragosa
 * Lich King

Other considerations
When upgrading using these Marks, the new piece of gear does not retain the enchants or gems of the old piece of gear.