Petrification

Petrification is a dark enchantment that can be placed on any moving being.

Description
Petrification induces a statuesque stillness and hardness in its victims. A Petrified individual will be as hard to harm as the hardest diamond, to the point that they are immune to the acidic properties of Basilisk Venom. However, an organic victim will not look any different when Petrified (things are somewhat different in the case of spirits, who will turn grayish upon Petrification).

Petrification is a well-documented magical phenomenon that seems to be a frequent result of weakened bursts of offensive magics, particularly ones meant to tamper with the soul such as a Basilisk's Gaze or a Killing Curse. A Gaze or Curse that has rebounded on a surface that absorbed part of its power will instead Petrify its target. Petrification is nonetheless not always accidental. Most famously, the Gorgon's Gaze, while too weak to kill like a Basilisk's, petrifies its victim (even through a reflection, interestingly enough). Various Dark Curses and items over the centuries have been purported to also induce Petrification in their targets, which, while not unlikely, remains unproven.

The only known ways of reverting Petrified individuals to life is to oint them (or, in the case of spirits, to sprinkle them) with either Mandrake Draught or Elixir of Life. In both cases, the victims have no recollection of their time being Petrified, and do not seem to have aged a day from when they were Petrified.

A somewhat more extreme method of freeing a Petrified being from their state is to kill them with a Killing Curse or some similar method. Once the soul of the being has been ejected from the body, the enchantment will fail and the Petrified body will revert to a limp corpse. Data is insufficient to say with certainty whether, should the deceased return as a ghost, the ghost would still be Petrified upon materializing.

Known Petrified Individuals

 * Gormless Morgan: 19th century. Petrified by a Gorgon he was attempting to assassinate, after their eyes met through a mirror.
 * Three Unknown Hogwarts Students: 1943. These three unknown young wizards and witches were Petrified by the rebounding Gaze of the Great Basilisk in 1943, and later revived with the use of Mandrake Draught.
 * Quirinus Quirrell: 1991-1993, Petrified by the Gaze of the Great Basilisk rebounding on the Mirror of Erised.
 * Tom Riddle: 1991-1993, Petrified along with Quirrell as his soul was sharing Quirrell's body at the time of the above events.