THE MINERAL DUFRENITE

  • Chemistry: Fe5(PO4)3(OH)5 - 2H2O, Hydrated Iron Phosphate Hydroxide.
  • Class: Phosphates
  • Uses: Only as mineral specimens.
  • Specimens

Dufrenite is a classic phosphate mineral. It is known from classic localities in Devon, England and elsewhere. Often associated with other rare minerals, dufrenite specimens can easily be a collectors favorite. Although not particularly colorful unless fresh, dufrenite's muted yellowish-brown color is none-the-less unique and distinctive. In fact, it produces a nice backdrop to the more colorful minerals that may be attached to the rounded botryoidal landscape.

PHYSICAL CHARACTERISTICS:

  • Color is yellowish-green or olive when fresh but turns brown when oxidized.
  • Luster is varied from vitreous or silky to dull or earthy.
  • Transparency: Specimens are translucent to transparent.
  • Crystal System is monoclinic; 2/m
  • Crystal Habits include botryoidal and globular masses or tabular crystals. Also found in radiating clusters and crusts.
  • Cleavage is perfect in two directions.
  • Fracture is uneven.
  • Hardness is 3.5 - 4.5
  • Specific Gravity is approximately 3.1 - 3.3 (slightly above average).
  • Streak is yellow-green.
  • Associated Minerals include hureaulite, laubmannite, kidwellite, quartz, limonite and rockbridgeite.
  • Notable Occurrences include Cornwall, England; Westphalia, Germany; Anglar, France and Cherokee County, Alabama, USA.
  • Best Field Indicators are crystal habit, color, associations and streak.
This Site Awarded
Available DUFRENITE specimens:
DUFRENITE specimen DUF-4
$ 90.00 -40% = $ 54.00
Dims: 2.45x1.86x1.58in (6.23x4.72x4.02cm) .... Wt: 4.3oz (122g) .... Loc: Three Oak Gap, Polk County, Arkansas, USA
While not particularly "pretty", this is a very interesting multi-mineral specimen, loaded with a variety of relatively rare iron phosphate hydroxides. I chose to categorize this as dufrenite because a careful inspection suggests that the bulk of the botryoidal formations are yellow-brown dufrenite (mostly earthy), although the surface is mostly olive-green kidwellite; they seem to have formed in layers. Accompanying them are many vitreous radiating fibrous crystals (all flat against the host rock) of brownish-red beraunite.
no photo
DUF-4
$ 54.00
no photo
see this List of ALL specimens including SOLD ones

 

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