leadnite

Leadnite is a mineral composed of lead and antimony sulfide. Its chemical formula is Pb2Sb2S5. Leadnite is a relatively rare mineral that typically occurs in hydrothermal veins. It is often found in association with other lead and antimony minerals, such as stibnite and bournonite. The mineral forms in moderate to low temperature hydrothermal environments.

Crystals of leadnite are usually prismatic or acicular, and they can be striated. The mineral is opaque and has a metallic luster. Its color ranges from dark gray to black. Leadnite is a relatively soft mineral, with a Mohs hardness of 2.5 to 3. It is also brittle and has a high specific gravity, around 6.7.

The mineral was first discovered in the Comstock Lode mining district in Nevada, USA, and was named after its chemical composition. Leadnite is not a significant ore of lead or antimony, but it is of interest to mineral collectors and geologists due to its rarity and characteristic crystal habit.

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