Definition: Minerals have been collected at Baveno for centuries. The locality,which gaveits name to the minerals bavenite and to the Baveno law for orthoclase twins,has producedsome of the world’s finest orthoclase crystals.巴韦诺双晶bā wéi nuò shuāng jīng...[继续阅读]

    Definition: An uncommon twin law applicable in feldspar,in which the twin plane andcomposition surface are. A Baveno twin usually consists of two individuals.巴韦诺双晶定律bāwéi nuò shuāng jīng dìng lǜ...[继续阅读]

    Definition: The Becke Line Test is a technique in optical mineralogy that helps determine therelative refractive index of two materials. It is done by lowering the stage (increasing the focaldistance) of the petrographic microscope and observing which dir...[继续阅读]

    Definition: The Berek compensator is an optical device that is capable of quantitativelydetermining the wavelength retardation of a crystal,fiber,mineral,plastic film or otherbirefringent material.贝累克补偿器bèi lèi kè bǔ cháng qì...[继续阅读]

    Definition: a chart used to determine the coordinates in reciprocal space of X-ray reflectionsthat produce贝尔纳图bèi ěr nà túOrigin: named after John Desmond Bernal,who created the diagram for interpreting X-rayphotographs...[继续阅读]

    Definition: a crystal of low symmetry in which the index ellipsoid has three unequal axes二轴晶èr zhóu jīngExample:Based on geometric construction and theoretical derivation,the directions of the two kinds ofoptical axes in the biaxial crystal have been dedu...[继续阅读]

    Definition: The couple of reflections h, k, l and ,, is called a Friedel pair, or Bijvoetpair. Their intensities are equal if there is no absorption,but differ otherwise. Friedel’s law thendoes not hold. Generally speaking,when absorption is prese...[继续阅读]

    Definition: In mathematics,a binary operation is a calculation involving two operands,inother words,an operation whose arity is two. Examples include the familiar arithmeticoperations of addition,subtraction,multiplication and division. More precisely,a b...[继续阅读]

    Definition: a prism having a highly obtuse angle to facilitate beam splitting双棱镜shuāngléng jìngExample:The distribution curves of light intensity of orthogonal biprism interference is made fromexperimental results.通过实验结果作出正交双棱镜干涉的光强度分布曲线。Extend...[继续阅读]

    Definition: An n-gonal bipyramid or dipyramid is a polyhedron formed by joining an ngonal pyramid and its mirror image base-to-base. The referenced n-gon in the name of thebipyramids is not an external face but an internal one,existing on the primary symm...[继续阅读]