The chemical formula of mineral Dufrenite is indicated by Fe5(PO4)3(OH)5 – 2H2O or Hydrated Iron Phosphate Hydroxide. Dufrenite is actually a Phosphate mineral. Dufrenite was named after Armand Small Dufrenoy (1792-1857), a French mineralogist and geologists. Mineral Dufrenite is known to crystallize in the monoclinic system. In optical mineralogy, the monoclinic system of crystal formation comprises crystals having three axes of unequal lengths. Two of which are usually found in a position that is oblique or not perpendicular to one another. However, both of which are commonly found perpendicular to the third axis.
Dufrenite is most commonly used as mineral specimen and it usually exhibits interesting microscope images under polarizing light microscopes used in optical mineralogy. Dufrenite mineral specimen can be actually easily considered as a favorite piece among mineral collectors because of its splendid appearance when evaluated with the aid of polarized light microscope for mineralogists. Fresh Dufrenite is most commonly found colorful most especially when viewed under petrographic polarizing light microscope. If found otherwise, the muted yellowish brown color of mineral Dufrenite is still considered distinctive and exquisitely unique and can be also found exhibiting a wonderful appearance under a petrographic polarizing light microscope. Dufrenite commonly form a nice and fascinating backdrop to the more colorful minerals, which can be possibly attached to the rounded botryoidal landscape. And this piece of material is commonly found having wonderful microscope images under petrographic polarizing light microscopes.
Dufrenite, when found fresh, most commonly appear yellowish green or olive that can be more interesting when evaluated under petrographic polarizing light microscope. However it will readily turn colored brown when oxidized. Dufrenite is most commonly found exhibiting a vitreous or silky to dull or earthy luster when viewed in reflected light of petrographic polarizing light microscope used in optical mineralogy. Mineral Dufrenite is most commonly found having a perfect cleavage in two directions when examined under polarizing microscope. Dufrenite also exhibits uneven fracture when it is evaluated under several minor adjustments on the aperture diaphragm of the petrographic polarizing microscope. The specific gravity measure of mineral Dufrenite usually gives an approximate value ranging from 3.1 gram per cubic centimeters to 3.3 grams per cubic centimeters, which is commonly considered slightly above average. The hardness measure of the mineral when it is evaluated using the Mohs scale method is usually ranging from 3.5 to 4.5. Dufrenite is most commonly found leaving a yellow green streak when specimen is rubbed on a white porcelain streak plate.
Most Dufrenite mineral crystals are found translucent to transparent in appearance. The crystal habits of the mineral Dufrenite as described in optical mineralogy field commonly include botryoidal and globular masses that are most commonly found exhibiting a nice and wonderful microscope appearance when viewed under polarized light microscopes. They can be also found in tabular crystals that are usually found splendidly exhibited when evaluated with the aid of petrographic polarizing microscope. Dufrenite can be also found exhibiting a splendid and fascinating radiating crystal clusters and crusts when viewed under polarized light microscope. Dufrenite mineral can be also found in blackish green color that is commonly very interesting when viewed under polarizing microscopes. Dufrenite is a ferric phosphate mineral that commonly occur massive or in nodules. Dufrenite is commonly found exhibiting a biaxial figure when viewed between crossed nicols of polarizing light microscopes. The dispersion display of mineral Dufrenite is relatively strong when it is evaluated in plane-polarized light of petrographic polarizing microscopes. Dufrenite is a non-fluorescent mineral in either long or short wave ultra violet light. The birefringence of mineral Dufrenite when viewed in plane light of petrographic polarizing light microscope used in optical mineralogy is usually found ranging from 0.0550 to 0.0830. Dufrenite is not radioactive mineral.
Mineral Dufrenite is commonly associated with several other wonderful minerals such as rockbridgeite, hureaulite, kidwellite, limonite, laubmannite and quartz. The best field indicators of mineral Dufrenite usually include color, streak, crystal habit and its wonderful association with other fascinating minerals. Mineral Dufrenite is considered as a classic phosphate mineral from several famous localities including Devon, England and many others. It is actually commonly associated with several other wonderful rare minerals. Mineral Dufrenite is commonly found in weathered ore deposits, with pegmatite phosphate minerals and also during limonite formations. It is considered as a secondary mineral. Mineral Dufrenite notably occurs at some famous mineral localities including Cornwall, England, Cherokee County in Alabama, USA
