User:GeoWriter/Sandbox5

=Analcimite= Analcimite is a type of igneous rock; it is a subvolcanic rock or an extrusive rock. It is composed mostly of the minerals analcime and titanaugite. Analcimite is a type of foidite. Varieties are olivine analcimite, leucocratic analcimite and augite analcimite. Chemically, although analcime is a sodium aluminium silicate mineral, analcimite is a ???potassic??? or an ???ultrapotassic??? alkaline igneous rock. It is ultramafic or mafic in the TAS classification (see TAS diagram).

Analcimite forms lava flows and volcanic plugs as well as subvolcanic dykes and sills.

There is also basanitic-analcimite - it occupies the same QAPF field as tephritic foidite. (Basanitic foidite has more than 10% CIPW normative olivine, tephritic foidite has less than 10%).

Examples

 * near Si Lake, Marion County, Oregon
 * Bald Hill near Wallan, Victoria, Australia
 * near Santo Antônio da Barra, in southwestern Goiás, Brazil - relict leucite crystals in this analcimite suggests it is actually altered leucitite.
 * Zákupy diatreme, Czech Republic
 * Trijebine, Serbia
 * near Cooktown, Queensland, Australia
 * Midland Valley of Scotland
 * Los Molinos, Cordoba Province, Argentina
 * near Meshkinshahr, Iran
 * Teic Dam, Iran
 * Tamazert, Morocco
 * Tubuai, French Polynesia
 * Makhtesh Ramon, Israel
 * Taiúva in the Bauru Basin of São Paulo (state), Brazil
 * Humphreys County, Mississippi
 * Ary-Dzhang in Arctic Siberia, Russia
 * Monroe Uplift, Arkansas
 * Spring Mountain volcanic plug near Glen Innes in NSW, Australia
 * Adrar, Mauritania
 * North Qilian Mountains, China (leucite-analcimite)