Truesilver Ore

Truesilver Ore is mined from Truesilver veins, with a minimum mining skill of 165.

Source
Truesilver Veins are found, uncommonly, wherever mithril veins are located. Rarely, they can be found as an alternative to a thorium vein.

Thousand Needles and othe places with Mithril are best lookouts.

Also found in Truesilver Veins
Rarely (~1%), these can be found in Truesilver veins:
 * Star Ruby
 * Aquamarine
 * Citrine

As an ingredient
Truesilver Ore is smelted into Truesilver Bars at a forge, requiring a mining skill of 165 or more.

Truesilver Ore cannot be prospected.

Background
Found anywhere silver can be mined, truesilver is also called "perfect silver" or "puresilver." Veins of this rare material are almost unknown. When found, truesilver deposits are usually situated deep within an exceptionally dense collection of ordinary silver. The substance can be immediately indentified by its azure color, in striking contrast to the duller ore around it.

Like lightforge iron, truesilver must be smelted in such a way that all impurities are removed. However, the material is much more forgiving. Still, there are additional difficulties inherent in using truesilver. Once it cools, it solidifies permanently and cannot be re-used. Attempts to reheat it simply turn it into a liquid state similar to that of mercury-and it never solidifies again. Thus, items forged of truesilver must be completed the first time. Thus, while truesilver is the most common of the rare materials, it is the most frustrating to work with. The floors of blacksmith shops across Azeroth are littered with truesilver junk.

Once forged, truesilver resembles ordinary silver except for a faint azure sheen. Truesilver possesses an unnatural attunement to the arcane. Weapons made of truesilver have an almost supernatural ability to slip through magical defenses. Armor made of truesilver increase the chances of the wearer casting a successful spell. Truesilver items must be magic; the fluid nature of the metal requires an enchantment of some sort to stabilize it.