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Related to syenite: trachyte


An igneous rock composed primarily of alkali feldspar together with other minerals, such as hornblende.

[Latin Syēnītēs (lapis), (stone) of Syene, from Syēnē, Syene, an ancient city of southern Egypt, from Greek Suēnē.]

sy′e·nit′ic (-nĭt′ĭk) adj.


(Geological Science) a light-coloured coarse-grained plutonic igneous rock consisting of feldspars with hornblende or biotite
[C18: from French syénite, from Latin syēnītēs lapis stone from Syene (Aswan), where it was originally quarried]
syenitic adj


(ˈsaɪ əˌnaɪt)

a granular igneous rock consisting chiefly of orthoclase and oligoclase.
[1790–1800; < Latin syēnītēs (lapis) (stone) of Syene]
sy`e•nit′ic (-ˈnɪt ɪk) adj.
References in classic literature ?
Copses of dates and dwarf-palms succeeded the dense forests; then vast, dry plains, dotted with scanty shrubs, and sown with great blocks of syenite.
It was then passing over Mabunguru, a stony country, strewn with blocks of syenite of a fine polish, and knobbed with huge bowlders and angular ridges of rock; conic masses, like the rocks of Karnak, studded the soil like so many Druidic dolmens; the bones of buffaloes and elephants whitened it here and there; but few trees could be seen, excepting in the east, where there were dense woods, among which a few villages lay half concealed.
Not far from Monte Video we passed through the village of Las Pietras, so named from some large rounded masses of syenite.
was approached with a new sort of freeness; a little Gerstley Borate here and a little Nepheline Syenite there gave me the sheen and shine that 1 was looking for.
Other extender pigments noted in commercial products include Nepheline Syenite, Kaolin, calcium carbonate, and, while not a traditional coating extender, ground tire rubber.
Granitic, syenite, hornblende and mica gneisses all look different--some are pink, some are gray, and some are a mix.
The studied rocks were concentrated biotite ("biotite") (Mogi das Cruzes, Sao Paulo State), nepheline syenite ("syenite") (Pocos de Caldas plateau, Minas Gerais State), and green banded argillite ("argillite") (Cedro de Abaete region, Minas Gerais State).
The host rock to these minerals, a coarse-grained nepheline syenite (Fig.
the country rock) in close proximity to the intrusions has been fenitized to varying degrees, producing quartz syenite, alkali syenite, nepheline syenite, pyroxene nephelinite, microcline syenite and albite syenite.
The chief metallic mineral resources include: gold, zinc, copper and tin-tungsten, while the chief non-metallic resources include: phosphate, high-grade silica sand, feldspar and nepheline syenite, kaolin, basalt and scoria, gypsum and anhydrite, limestone and dolomite, ornamental stone and quartz.
The Tajno massif is composed of alkaline rocks ranging from syenite to pyroxenite, cut by carbonatite veins (Krystkiewicz & Krzeminski 1992; Ryka 1992; Ryka et al.