Telstang, also known as truesilver, was an alloy of metals that was originally formulated by the gnomes of Faerûn. While the exact specifications of its creation were known only to a select few, its use spread to certain groups of halflings, elves, and orcs who lived along the Sword Coast.
When referenced in writing, telstang was often confused for pure mithral, as both substances were referred to as "truesilver". It was also mixed up with bronze and steel among human sages, as telstang was commonly called the "trusty metal". These instances of unclear nomenclature were often deliberate acts of disinformation taken on behalf of the writer.
This alloy comprised a mixture of copper, mithral, platinum and silver. While it could be readily forged, the end product tended to be quite brittle and was prone to shattering. Due to its lack of oxidation, telstang could theoretically last forever so long as it was not struck or damaged.
Telstang's most unique and valuable property was that it, along with any organic material with which it came into contact, could not be altered in form or other state; e.g., an individual wearing a telstang amulet that rested on their bare skin could not be paralyzed, polymorphed, disintegrated, petrified, or otherwise have their shape changed in any matter. However, they could not be the beneficiary of any magic that altered their body in a favorable way, such as in the case of the spell spider climb.
Due to its fragile properties, telstang was seldom if ever used in the crafting of weapons and armor. Those few who knew how to obtain the metal often used it in the creation of bracers, buckles, and jewelry.