Sideromelane

Reticulite from Kilauea volcano in Hawaii

Sideromelane is a

vitreous Vitreous may refer to: Materials * Glass, an amorphous solid material ** Vitreous enamel, a material made by fusing powdered glass to a substrate by firing * Vitreous lustre, a glassy luster or sheen on a mineral surface Biology * Vitreous body, ...

basaltic volcanic glass, usually occurring in palagonite tuff, for which it is characteristic. It is a less common form of tachylite, with which it usually occurs together; however it lacks the

iron oxide Iron oxides are chemical compounds composed of iron and oxygen. Several iron oxides are recognized. All are black magnetic solids. Often they are non-stoichiometric. Oxyhydroxides are a related class of compounds, perhaps the best known of whic ...

crystals dispersed in the glass, and therefore appearing transparent and pure, with yellow-brown color, instead of tachylite opaque black. It forms at higher temperatures and with more rapid chilling. Presence of sideromelane indicates higher temperature of the lava, and solidifying of the flow closer to the vent, probably by rapid quenching in a wet environment. Sideromelane often forms during explosions of

submarine volcano Submarine volcanoes are underwater vents or fissures in the Earth's surface from which magma can erupt. Many submarine volcanoes are located near areas of tectonic plate formation, known as mid-ocean ridges. The volcanoes at mid-ocean ridges ...

es and

subglacial volcano A subglacial volcano, also known as a glaciovolcano, is a volcanic form produced by subglacial eruptions or eruptions beneath the surface of a glacier or ice sheet which is then melted into a lake by the rising lava. Today they are most ...

es, and often occurs as fragments embedded in a palagonite matrix, forming hyaloclastite deposits. Sideromelane is a mafic rock. Vitreous rocks {{Volcanology-stub