Ijolite
_(14822252052).jpg){kind=link}
Ijolite is an igneous rock consisting essentially of nepheline and augite.[1] Ijolite is a rare rock type of considerable importance from a mineralogical and petrological standpoint. The word is derived from the first syllable of the Finnish words such as Iivaara, IijokiTemplate:, and Ii, all geographical names in Finland, and the Ancient Greek Xiflos, a stone. Ijolite occurs in various parts of the Kainuu region of eastern Finland and in the Kola Peninsula of northwest Russia on the shores of the White Sea.Template:Sfn Ijolite was first defined and named by Finnish geologist Wilhelm Ramsay.[2]
The pyroxene is Template:Clarify span, yellow or green, and is surrounded by formless areas of nepheline. The accessory minerals are apatite, cancrinite, calcite, titanite and schorlomite, a dark-brown titaniferous variety of melanite-garnet. This rock is the plutonic and holo-crystalline analogue of the nephelinites -volcanic equivalent and nepheline-dolerites; it bears the same relation to them as the nepheline syenites have to the phonolites.Template:Sfn
A leucite-augite rock, resembling ijolite except in containing leucite in place of nepheline, is known to occur at Shonkin Creek, near Fort Benton, Montana, and was earlier called missourite,Template:Sfn but is now regarded as a variety of leucitite.[3]
References
<templatestyles src="Reflist/styles.css" />
Script error: No such module "Check for unknown parameters".
- This article incorporates text from a publication now in the public domain: Script error: No such module "template wrapper".
