eulytine

{{Infobox mineral | name = Eulytine | category = Silicate mineral | boxwidth = | boxbgcolor = | image = Eulytine-122715.jpg | imagesize = 220px | caption = Eulytine spheroids (agricolites) (Baden-Württemberg, Germany) | formula = Bi4(SiO4)3 or Bi4Si3O12 | IMAsymbol= Eul | molweight = | strunz = 9.AD.40 | system = Cubic | class = Silicate | symmetry = | color = orange or orange-brown to red-brown, less often bright green or colorless | habit = generally bright is appearance | twinning = penetrations twins on {001}. | cleavage = imperfect to fair {110} | fracture = irregular to uneven, vaguely conchoidal, the mineral is brittle | tenacity = brittle | mohs = 4.5 | luster = diamond to glass | polish = | refractive = | opticalprop = | birefringence = | dispersion = | pleochroism = non-pleochroic | fluorescence= | absorption = | streak = white to grayish yellow | gravity = | density = 6.1–6.6 (calculated) | melt = | fusibility = | diagnostic = | solubility = | diaphaneity = transparent to opaque | other = | references = }} Eulytine ( from , fusible, easily dissolved) or bismuth blende (obsolete) is one of the rarest minerals in nature. The composition is bismuth silicate with the calculation formula Bi4(SiO4)3 or Bi4Si3O12. The mineral forms isometric cubic crystals up to 2 mm in size, the supporting form of which is a tetrahedron or tristetrahedron. Among the varieties, there are also often concentric, fibrous or spherical aggregates of a very impressive appearance, which were previously called agricolites.

Eulytine is a secondary mineral, a product of the oxidation of bismuth and its compounds.