See boehmite.

An obsolete term for a greasy clay with iron oxide impurities that produce a red, yellow and/or brown color and with about 24% water, possibly primarily halloysite.
Syn. “bergseife” for “mountain soap”, also obsolete

Born repulsion forces are described as a strong, short-range repulsion term for bond energy between two charged ions. Born repulsion forces arise when neighboring ions approach sufficiently close so that the electron clouds involving the inner electron orbitals begin to overlap, thereby forcing higher energy states owing to the Pauli exclusion principle. The term increases exponentially as orbital interpenetration increases with the decrease in interionic distance.

A boron-rich member of chlorite with an ideal chemical composition of Li_1+3xAl_4-x(BSi₃)O₁₀(OH,F)₈ where x = 0.0 to 0.33 atoms per formula unit (Zagorsky et al., 2003). Borocookeite occurs as the Ia polytype. Borocookeite has been found in miarolitic cavities at temperatures greater than 240-265^oC in pegmatite deposits, such as in the Krasny Chikoy district, Chita region, Russia.
Cf., manandonite, boromuscovite

A dioctahedral member of the true mica group. The end-member formula is KAl₂□BSi₃O₁₀(OH)₂, where □ = vacancy. Boromuscovite occurs as 2M₁ and 1M polytypes and has been found in pegmatites at the Řečice pegmatite dikes, Czech Republic, where it occurs asfine-grained masses, and Little Three Mine pegmatite dike, San Diego County, California, USA, where it occurs as coatings from late-stage hydrothermal fluids.
Cf., borocookeite, manandonite, muscovite

The fused, amorphous, siliceous residue from burning coal in industrial burners. Crushed and sized bottom ash is used as an aggregate substitute in concrete and as a non-crystalline substitute for quartz sand in sand blasting.
Cf., fly ash

A transparent, yellow green variety of massive serpentine (antigorite?), used as an alternative for jade. Bowenite is not a mineral name and should not be used in the scientific literature.
Syn. tangiwaite or tangawaite (from New Zealand)

An obsolete term for bityite.

An obsolete term for a saponite-rich material from near Bowling, Dumbarton, Scotland.

Bragg’s law describes the condition for an X-ray reflection (i.e., constructive interference) for crystalline materials and is given as n λ = 2 d sinθ, where n is the path difference between reflecting planes, which must be an integer for constructive interference, λ is the wavelength, d is the interplanar spacing, and θ is the glancing angle of incidence (reflection angle). In an X-ray diffraction experiment, the λ is known and is dependent on the X-ray source in use,θ is the measured quantity, and d is the parameter that is characteristic of the material under study. Thus, both n and d are unknowns. In practice, the order of the reflection n is fixed for the value of d for a specific plane hkl (and thus is included in the value) and, the use of d_hkl symbolizes this inter-relationship. Thus, the modified version of the Bragg equation is used in practice, which is given as: λ = 2 d_hkl sinθ.