Augelite

Augelite was an ornamental stone found in Faerûn. It was used by Uthgardt barbarians for adornment, and worn by priests of Akadi for jewelry and holy symbols.

Description
This gemstone was transparent, colorless, and soft enough to carve without special tools or exceptional skill, but too soft for intricate carving because it tended to split. A typical specimen had a base value of 10 gp.

Powers
The power of this stone was its antipathy to magic. Spells were slightly easier to resist, and magically-induced injury was slightly lessened within a 10 ft (3 m) radius around an augelite gem.