What is a mineral of a lead-gray color and brilliant metallic luster, occurring in prismatic crystals; sulphide of antimony; -- called also antimony glance, and gray antimony called?

stibnite — A mineral of a lead-gray color and brilliant metallic luster, occurring in prismatic crystals; sulphide of antimony; -- called also antimony glance, and gray antimony. (Webster's 1913.)

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