Beljuril

Beljurils, also known as fireflashils, were gemstones unique to the Realms. They were a deep seawater green and all known specimens were roughly the size of a human fist and not quite spherical. About once every hour (rates vary from stone to stone) a beljuril would absorb an undetectable amount of energy from within a thirty foot (ten meter) radius and re-emit that energy as a "flash" of sparkling light without heat, sound, or electrical discharge. The light produced was easily noticeable when the ambient light was dim (candlelight or lantern light) and in the dark it was dazzling to the eye. Beljurils were very difficult to cut with metal tools and the stone was very durable. They were sometimes claw-mounted to shoulder-plates or worn in a pectoral, or used as decorative lighting or beacons by the wealthy. They were found in ancient rock, usually blue claystone.