Skydrop

Skydrop was the common name given to tektite material; fragments of glass of meteoric origin found beneath the shifting dunes of Anauroch and other deserts.

Description
Skydrop stones were usually clear to lightly shaded with a glassy luster. These stones were left uncut and merely polished and mounted in a claw setting as earrings and pendants. A typical specimen had a base value of 50 gp.

Powers
A creature touching, wearing, or carrying a skydrop gemstone was immune to petrification.