- "Most precious of all substances, the pulse of our life. If the Horned Rat is our father, then surely, Warpstone is our mother. Its uses are infinite. Like the heart of an endless fire, it is. Even the smallest of pieces will continue to give power indefinitely, allowing many of our devices to become somewhat portable. Warpstone fire can not only consume a substance, but actually change it’s structure to far more than just ‘burned’ due to exposure to it’s holy flames. Weapons made from Warpstone produce their own poison. A Warpstone charm brings real luck, changing what ‘was to be’ to what ‘might have been’ with none the wiser. So where does it come from? There are those among the more superstitious of our folk and a few foolish Grey Seers that believe Warpstone is the leavings of the Horned Rat. I subscribe to the secular view – that it is chunks of the dark moon, Morskrit, which has managed to gift us with pieces of its essence. Dangerous it is; to touch Warpstone often. But that’s what slaves are for, yes-yes?"
- —Narshift, Warlock Engineer of Clan Skryre
Warpstone is therefore very rare, and can be found, smuggled, or bought into the the Old World in many different ways. Powdered Warpstone on the other hand, are sometimes drawn south from the unnatural winds of the Northern Wastes, carrying with it furious storm of wild Dark Magic that sows terror and destruction upon many parts of the southern lands. Most Warpstones fall to earth as meteorites from the sinister Chaos-Moon Morrslieb with the majority of the substance falling into the harsh domains of the Dark Lands. Warpstones can also be formed and crystallize from a sufficiently powerful current of Dark Magic into small pieces by very powerful Sorcerors or Magicians. Being the source of all magic, Warpstone is highly coveted by magicians, alchemists and sorcerers for its false properties of turning lead into gold and healing the sick and wounded. Most Warpstone is more commonly found in Meteorites than in any other location in the known world. Meteorites usually have a larger abundance of Warpstones than ordinary deposits, but they are sometimes irregular in shapes and sizes, and require refinement before being used for rituals or other evil-minded uses.
But to any other race within the Old World, no nation has so much great use or need of Warpstone then the great Skaven Under-Empire. The role of Warpstone in Skaven society is diverse, serving as a source of energy both for their twisted magic, advanced technology, and even as key ingredients to be used in their breeding and mutation experiments. Skavens have been known to incorporate Warpstone into piece of armor or jewelry to add a magical property to their otherwise normal gear. Warpstone has also been in use as an ingredient in magical potions or deadly poison. It has also been widely used as a form of currency within Skaven society, in the form of Warpstone Tokens -- a refined and minted piece of coin made entirely of pure Warpstone.
It is difficult to determine the exact physical form most Warpstones take, but many have noted that nearly all Warpstone has a black and greenish glow to them. Warpstones has also been noted to having no characteristic odor and is slightly warm to the touch. Those more unrefined Warpstones are naturally very dangerous for all creatures; prolonged exposure to the substance will lead to madness, mutation and eventual death. Prolonged consumption produces an addiction much greater than any other natural drug, an addiction that never ceases and will always plague those users for all eternity.
- Warhammer Armies: Skaven (7th Edition)