Bitotie Granite Isotropic Or Anisotropic

Sometimes we call muscovite as white mica and biotite as black mica.

Bitotie granite isotropic or anisotropic. A very simple example of anisotropy is wood. Large grains or fine fibrous masses of hornblende may mantle or replace pyroxene. Biotite grain size is of the order of 0 3 mm and constitutes 3 5 of this rock. Granite gneiss migmatite biotite m hornblende gneiss q quartzite quartz schist su gneiss schist complex bs biotite garnet schist.

Biotite is a common group of phyllosilicate minerals within the mica group with the approximate chemical formula k mg fe 3 alsi 3 o 10 f oh 2 it is primarily a solid solution series between the iron endmember annite and the magnesium endmember phlogopite. The red brown biotite in this graphite and garnet bearing granite has high titanium and low fe 3 content. Anisotropic if the value of a vector measurement of its resistivity varies with direction taylor and flemming. Anisotropic gems anisotropy anisotropism.

They have many similarities as well as some differences. Plane polarized light field width is 0 6 mm. Also found as micaceous or tabular grains or grains with irregular outline. The simple definition of anisotropy or less commonly anisotropism is exhibiting different values of a particular property of a material when measured in different directions as opposed to isotropy.

Also found as anhedral to strongly irregular grains which in some cases may poikilitically enclose associated minerals. Grains may be bent particularly in metamorphic rocks. Especially biotite can contribute to the bulk rock elastic anisotropy significantly kern wenk 1990 as shows its single crystal elastic anisotropy of 44 per cent simmons wang 1971. The odds of a grain lying in just the.

The mineral grain size of laurentian granite varies from 0 2 to 2 mm with the average quartz grain size of 0 5 mm and the average feldspar grain size of 0 4 mm with feldspar being the dominant mineral 60 followed by quartz 33. A complication arises because anisotropic minerals will appear isotropic if grains are oriented in a specific way if they are oriented so they are viewed down an optic axis additionally as the microscope stage is rotated anisotropic minerals in any orientation go extinct turn black every 90 o. In addition to cpo biotite and muscovite spo has been found to contribute significantly to the bulk rock elastic anisotropy kern et al 2009. More aluminous end members include siderophyllite and eastonite biotite was regarded as a mineral species by the international.

Muscovite and biotite are phyllosilicate minerals. This patch of biotite shows a range of pleochroic colors caused by different crystal orientations.