Geologists study the earth in order to understand its processes and to extract valuable resources. X-ray diffraction (XRD) analysis provides a multitude of information about crystalline phases within rocks, which is essential to understanding their mineralogy, chemistry, and formation conditions. XRD data provides direct information about the identity of crystalline phases, their relative abundances, crystallite size, strain, and site chemistry.
Historically, the mineralogy of rocks was evaluated via polarized light microscopy (PLM) of thin sections or back-calculated from chemical data. The error in these methods is much larger than that of XRD, and preparation of samples for XRD is much simpler and less time consuming than for optical methods. XRD data can be used to distinguish between polymorphs and accurately identify the distribution of cations within the minerals making it the preferred method of geoscientists.
Scan of lanthanum hexaboride (LaB₆)
Low-angle scan of silver(I) behenate nanocrystals
The performance characteristics of cement are directly related to its phase composition. For example, ASTM type III cement develops high early strength and is characterized by having a larger mass fraction of alite. In comparison, ASTM type IV cement is known to have a low heat of hydration and is characterized by having a much lower mass fraction of alite.
Corrosion reduces structural integrity and can ultimately lead to part failure. Furthermore, both scale and corrosion products can result in blockages, necessitating costly downtime and repairs. Powder x-ray diffraction (XRD) is a powerful technique that allows rapid identification of scale and corrosion products. While chemical analysis methods can be used to determine elemental composition, they cannot identify what phases are present in scale and corrosion products.