cubanite

{{Infobox mineral | name = Cubanite | boxwidth = | boxbgcolor = | image = Cubanite-47299.jpg | imagesize = 260px | alt = | caption = Striated, cyclically-twinned cubanite crystals from the Chibougamau mines of Quebec (size: 1.5 × 1.3 × 1.0 cm) | category = Sulfide mineral | formula = CuFe2S3 | IMAsymbol=Cbn | molweight = | strunz = 2.CB.55a | dana = | system = Orthorhombic | class = Dipyramidal (mmm) H-M symbol: (2/m 2/m 2/m) | symmetry = Pcmn | unit cell = a = 6.467(1) Å, b = 11.117(1) Å, c = 6.231(2) Å; Z = 4 | color = Bronze to brass-yellow | colour = | habit = Crystals elongated to thick tabular, striated also massive | twinning = Common with twin plane {110} in pairs, also as fourlings and pseudohexagonal sixlings | cleavage = Parting on {110} and {10} | fracture = Conchoidal | tenacity = | mohs = 3.5–4 | luster = Metallic | streak = Black | diaphaneity = Opaque | gravity = 4.0–4.2 | density = | polish = | opticalprop = Distinctly anisotropic on polished surface | refractive = | birefringence = | pleochroism = | 2V = | dispersion = | extinction = | length fast/slow = | fluorescence = | absorption = | melt = | fusibility = | diagnostic = | solubility = | impurities = | alteration = | other = Strongly magnetic | references = }}

Cubanite is a copper iron sulfide mineral that commonly occurs as a minor alteration mineral in magmatic sulfide deposits. It has the chemical formula CuFe2S3 and when found, it has a bronze to brass-yellow appearance. On the Mohs hardness scale, cubanite falls between 3.5 and 4 and has a orthorhombic crystal system. Cubanite is chemically similar to chalcopyrite; however, it is the less common copper iron sulfide mineral due to crystallization requirements.