Also found in: Encyclopedia, Wikipedia.
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.
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.
Among the additives options that prevent thin plastic layers from sticking to each other, 'Talc, nepheline syenite, and DE have been the incumbent high-performance antiblock minerals in plastic films," says John Flurley, president and CEO of Trinity Resources.
Transparent Ferro Frit # 3195 50 Custer feldspar 21 Flint 325x 16 EPK day 8 Whiting 5 Bentonite 2 Zam #15 Opaque Matt Nepheline syenite 270x 45 Whiting 18 EPK day 20 Flint 325x 5 Zinc oxide 12 Bentonite 2
PRODUCT OVERVIEW II-21 Properties of Soda Ash II-21 Toxicity and Handling II-21 Packaging and Storage II-21 End-Use Profile II-21 Natural Soda Ash - Occurrence, Mining and Processing II-21 Trona - A Rare Mineral II-22 Green River Basin - The Largest Source of Trona II-22 Processing of Natural Soda Ash II-22 Natural Soda Ash Refining II-22 FMC's Solution Mining Technology II-22 Synthetic Soda Ash - Production Processes II-23 The Solvay Process II-23 Dry Liming II-23 Nepheline Syenite Process II-23 Carbonation of Caustic Soda II-23 Major Input/Output Levels of Soda Ash Process II-24 A Comparison of Select Soda Ash Technology II-24 3.
distributor is Maroon Group, Avon, Ohio) is said to combine the best attributes of talc, nepheline syenite (NS), and diatomaceous earth (DE).
Other resources are Nepheline Syenite, phosphates, gemstones, and metallic minerals including gold and base metals and variety of other industrial minerals.
UC RUSAL's nepheline syenite production was 4,662 thousand tonnes in 2013, as compared to 4,947 thousand tonnes in 2012 (a decrease of 6%).
At the Jupiter prospect, the 14 diamond drill holes completed during the quarter continued the broad spaced testing of the 2km long structural corridor as well as selected holes being drilled to follow up the high grade mineralisation intersected previously in the Heffernan's syenite.