Diamond

Diamonds are among the most valuable and rare gemstones in the world. They are powerful and multi-purpose magical reagents, required for many sophisticated wizard spells that were commonplace in the industries and economies of the civilized world before the Age of Apocalypse. Nowadays diamonds are even more precious, for it is largely thanks to magic that mortal civilization has managed to endure on the broken world of Amanor.
Only diamond harvested from nature has magical properties. Mortal spellcraft is advanced enough to allow the transmutation of other materials into diamond, but the material thus created simply does not function as a magical reagent. This frustrating phenomenon makes natural diamond a non-renewable resource as far spellcasting is concerned. For this reason, before the Age of Apocalypse, many nations enforced laws that monopolized the trade of natural diamonds to the state or prohibited the use of natural diamonds in jewelcrafting. Such rare pieces of jewelry that were crafted with natural diamonds were, or course, outlandishly expensive.
In the Age of Apocalypse, there are no active sources of diamond in the whole Circle of the World. It was the dwarves of Baruk-Tel that supplied the civilizations of the Heartlands with diamonds in the past, but that great kingdom has long since shattered -- the monolithic mountain that was its namesake reduced to gravel. Where Baruk-Tel once stood lies now only the great lake known as Harrowmere. Ghosts of countless dwarven dead haunt those dismal shores, keeping away all eager prospectors and dungeoneers that would seek to reclaim the lost riches of the Kingdom Under The Mountain.
In the west of Circle of the World, in The Twilight before the World's Edge, the people known as Westerlings survive in their harsh land only thanks to magic. Fortunately for them, their fallen nation was a forerunner in wizardry before the Age of Apocalypse. The Glacier has swallowed their cities and their diamond mines, and so the Westerlings must regularly brave the dangers of that lightless wasteland, venturing into the ruins of the past in search of the priceless gemstones that are the lifeline of their people.

Type

Mineral / gemstone

Value

Extremely valuable (nearly priceless), essential for wizardry.

Rarity

Extremely rare, no known sources available.

Color

Typically yellow, brown, or gray to colorless.

Common State

Rough stone that must is cut into diamond gemstones.

Known deposit locations
Island of Typhe in the World's Edge
Bottom of Harrowmere lake
Common usage
Component in advanced spellcasting
Jewelcrafting