Ravenar

Ravenar, also called schorl, was a variety of tourmaline mainly in demand in the North, and less so in other lands.

Description
Ravenar occurred in long crystals like other varieties of tourmaline and was a solid gloss black. Ravenar was commonly used for inlay work on weapons and accouterments. Where it was popular, a typical specimen had a base value of 1,000 gp.

Powers
Ravenar, like all tourmalines, could absorb any spell cast upon it and immediately convert it into three lightning bolts that blasted outward in straight lines from the crystal facets in directions chosen by the caster. This act consumed the gem in the process.

Trivia
Ravenars were considered prized gems among the drow. Their lesser deity Vhaeraun was known to occasionally send ravenars to show his favour or disfavour to his followers.