The Epidote structure consists of octahedral AlO6 groups sharing edges to form continuous chain parallel to b axis. In one-third of the octahedral groups, Al 3+ is surrounded by four O 2- and two (OH) - .

Epidote is characterized by its green color and one perfect cleavage. H= 6-7. G = 3.25 to 4.45. Streak is white to gray. Clinozoisite and epidote are distinguised from eachother by optic sign, birefringence, and color.

Clinozoisite-Epidote thin section photomicrographs are taken in plane-polarized light and cross-polarized light, and can easily be recognized under the microscope.

Epidote. Comments: Dark green, blocky epidote with transparent quartz. Location: Copper Mt., Prince of Wales, Alaska. Scale: 7 x 5 cm. © Fabre Minerals

Relief: Epidote exhibits high relief in thin section, making it stand out prominently from surrounding minerals. Cleavage: Epidote shows one perfect cleavage parallel to the elongation of the grains.

Epidote in thin section Epidote is generally characterized by a prismatic habit with six-sided ‘basal’ sections. Epidote has a single set of cleavage planes oriented parallel to the long axis.

Note several bubbles introduced when the thin section was made. The field of view is about 3.5 mm. This specimen comes from Keweenaw County, Michigan. The photos show pleochroic hornblende (green hues; PP) and epidote (clear; PP) in a mafic schist.

The preceding pictures and videos are of epidote in epidosite and unakite, where it’s quite easy to spot. You’re more likely to encounter epidote as a tiny, easily overlooked accessory mineral; the following pictures and videos are of tiny, easily overlooked accessory epidote. Epidote grain, PPL

However, it is important to make a polished thin section or a polished section to identify the opaque minerals that occur associated with epidote . Sample preparation : epidote, when in very small crystals, acquires a very good polishing quite easily.

2022年8月28日 · In thin section, epidote has high relief and is usually colorless, but may be light green or pink and pleochroic, depending on composition. Interference colors range up to third order as Fe content increases. Football-shaped grains with concentric interference color rings are diagnostic of epidote.