- or to hide it,
depending on the
colors and
their attractiveness. The
pleochroic colors are at
their maximum when
light is
polarized parallel with a prin****l...
- A
pleochroic halo, or radiohalo, is a microscopic,
spherical s**** of
discolouration (pleochroism)
within minerals such as
biotite that
occurs in granite...
-
through prolonged annealing. A
related phenomenon is the
formation of
pleochroic halos surrounding minute zircon inclusions within a
crystal of biotite...
-
trace amounts of
impurities can tint crystals, and it can be
strongly pleochroic.
Every color of the
rainbow may be
represented by elbaite, some exhibiting...
- U,H,etc... concentrations.
Solubility Insoluble Other characteristics Fluorescent and radioactive, May form
pleochroic halos, Relief: high References...
-
widely used by
experienced gemologists. With the
polarizing type, only one
pleochroic color can be seen at a time. This
makes the
process time-consuming and...
-
amorphous (metamict state); the
optical result,
termed a
radioactive halo or
pleochroic halo, is
observable with
various techniques, such as thin-section petrography...
-
allanite results in some
interesting phenomena.
Allanite often has a
pleochroic halo of
radiation damage in the
minerals immediately adjacent. Also highly...
- moderate. It is
colorless in
plane polarized light, and it is
weakly pleochroic.
Perite is
found in
areas near
igneous extrusions in
places like the Western...
- yellowish-green or pistachio-green. It
displays strong pleochroism, the
pleochroic colors being usually green,
yellow and brown.
Clinozoisite is green, white...
