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Jamesonite
Chemical Formula	Pb4FeSb6S14
Species	Sulfides
Crystal System	Monoclinic
Mohs Scale	2
Specific Gravity	5.63
Color	gray-black
Streak	gray-black
Luster	Metallic
Diaphaneity	Opaque
Cleavage	Distinct/Good good; also possibly amd
Crystal Habit：Acicular to fibrous and striated parallel . In felted masses of needles. Also massive, fibrous to columnar; radial or plumose at times. In subparallel aggregates of prismatic crystals, forming a columnar mass.
Geological Setting：Late stage hydrothermal mineral formed at moderate to low temperature.

Jamesonite is a sulfosalt mineral, a lead, iron, antimony sulfide with formula Pb₄FeSb₆S₁₄. With the addition of manganese it forms a series with benavidesite. It is a dark grey metallic mineral which forms acicular prismatic monoclinic crystals. It is soft with a Mohs hardness of 2.5 and has a specific gravity of 5.5 - 5.6. It is one of the few sulfide minerals to form fibrous or needle like crystals. It can also form large prismatic crystals similar to stibnite with which it can be associated. It is usually found in low to moderate temperature hydrothermal deposits.

It was named for Scottish mineralogist Robert Jameson (1774-1854). It was first identified in 1825 in Cornwall, England. It is also reported from South Dakota and Arkansas, USA; Zacatecas, Mexico; and Romania.