How clay minerals are classified?
These minerals can be classified on the basis of variations of chemical composition and atomic structure into nine groups: (1) kaolin-serpentine (kaolinite, halloysite, lizardite, chrysotile), (2) pyrophyllite-talc, (3) mica (illite, glauconite, celadonite), (4) vermiculite, (5) smectite (montmorillonite, nontronite.
Which clay has the most minerals?
Illite
Illite is similar to muscovite and is the most common clay mineral, often composing more than 50 percent of the clay- mineral suite in the deep sea.
How do you identify clay minerals in XRD?
Identification of Clays using XRD Basal reflections give d-spacing of the basal layer which represent the thickness of the silicate layers and the unit cell often contains multiple layers. Clay mineral peaks can generally be distinguished by the width halfway up the peak (i.e. the full width at half maximum, FWHM).
What is the difference between clay and clay minerals?
Clay is natural, fine-grained (<2 or <4 μm), mainly constituted of phyllosilicates, plastic (except flint clays), and hardens on drying or firing. On the other hand, clay mineral is natural or synthetic, without size criterion, might include nonphyllosilicates, plastic, and hardens on drying or firing.
What is clay and its classification?
Ceramic clays are classified into five classes; earthenware clays, stoneware clays, ball clays, fire clays and porcelain clays. Earthenware clays contain iron and other mineral impurities which cause the clay to reach optimum hardness at between 1745°F and 2012°F (950°C and 1100°C).
What is a 1 1 clay mineral?
A 1:1 clay would consist of one tetrahedral sheet and one octahedral sheet, and examples would be kaolinite and serpentinite. A 2:1 clay consists of an octahedral sheet sandwiched between two tetrahedral sheets, and examples are talc, vermiculite, and montmorillonite.
How do you identify minerals from XRD peaks?
Generally, the method of identifying a mineral from its X-ray diffraction pattern is to first label the peak positions according to their 20 values, and then to compare the numbers obtained for the three highest peaks with those of various minerals.
What are the principles of clay mineral analysis?
Principles and applications of these methods are focused upon in addition to related differences in the analysis of clay minerals (i.e., sample preparation, the selection of characteristic reflections for quantification and standards added during analysis).
How is XRD used to analyze clay minerals?
XRD-based quantitative analysis of clay minerals using reference intensity ratios, mineral intensity factors, Rietveld, and full pattern summation methods: A critical review
What kind of minerals are found in clay?
Traditionally, two types of internal standard minerals, corundum (α -Al 2 O 3) and zincite (ZnO) are applied to quantify clay-rich samples.