Voidglass

Grioths wield weapons fashioned from a strange sort of transparent material called voidglass. This material is as hard as steel, but made of crystals that voidglass shapers on unknown worlds grow into the desired shapes. Voidglass resonates with a creature’s mind, bolstering thought and mental defenses. Any suit of armor normally made from metal can be made of voidglass. A suit of light voidglass armor grants a +1 resistance bonus on all saving throws against mind-affecting magic. This bonus increases to +2 for medium voidglass armor, and +3 for heavy voidglass armor. Voidglass armor isn’t often worn by grioths, but voidglass weapons are another story. The creatures (and perhaps other strange beings with similar psychic capabilities) can funnel violent bursts of psychic energy through these weapons on a hit (see page 62). In the hands of any creature, a voidglass piercing or slashing weapon deals 1 additional damage on a hit-bludgeoning weapons gain no benefit. Voidglass has 30 hit points per inch of thickness and hardness 10. A pound of raw, unworked voidglass is worth 100 gp.