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Related to illite: kaolinite, Muscovite, Montmorillonite, chlorite, Smectite


(Minerals) a clay mineral of the mica group, found in shales and mudstones. Crystal structure: monoclinic. Formula: K1–1.5Al4(Si6.5–7Al1–1.5O20)(OH)4
[C20: named after Illinois, where it was first found]


(ˈɪl aɪt)

any of a group of clay minerals, hydrous potassium aluminosilicates, characterized by a three-layer micalike structure and a gray, light green, or yellowish brown color.
[1937; Ill(inois) + -ite1]
il•lit•ic (ɪˈlɪt ɪk) adj.
References in periodicals archive ?
The qualitative and quantitative X-ray diffraction analysis established that its major minerals include detrital minerals like quartz and feldspars, with an average content of 45%, as well as clay minerals like kaolinite, andreattite and illite, with an average content of 37% (Table 1).
Compared to sandstones present in the E6 structure, sandstones in the E7 structure in some parts of the Deimena Formation contain more clay and carbonate minerals, including ankerite, dolomite, admixture of feldspar and clay fraction represented by kaolinite and illite.
Clay minerals in facing water are active (absorbing water and swelling potential) and inactive, Shales often have inactive Clay minerals such as Kaolinite, Illite and active minerals such as Montmorilonite.
The specific influences are as the following several aspects: (1) the weathering degree of subgrade filling: the content of hydrophilic clay minerals in weathered debris , like montmorillonite, illite, kaolinite, etc are different as the different of weathering degree.
The latter varied from illite (PDF24-495) to muscovite (PDF 80-743).
The mineralogical composition of the sample is dominated by calcite, quartz and illite.
Brown Algae Extract & Illite Clay Suspension is added for a strong anti-inflammatory.
Kaolinite, illite, quartz, microcline, dickite, mordenite, gamma alumina and iron rich minerals, such as pyrite and hematite, constituted the mineral makeup.
Using distilled water, researchers prepared 1-liter suspensions of bentonite, kaolinite, and illite (typical clays of tropical regions) with turbidities of 50, 100, and 200 nephelometric turbidity units (NTU).
XRD analysis revealed that Sevier Shale is composed of quartz, orthoclase, microcline, calcite, gypsum, chlorite, illite, and mixed layers of kaolinitemontmorillonite (Fig.
The kaolinite in this study contained some illite which may have increased the pH 7 cation exchange capacities to 17.