Xenophyllite is a rare phosphate mineral typically appearing as yellow to greenish-yellow lamellar or platy crystals. It is most commonly found in specific hydrothermal vein environments, often occurring in association with other phosphate minerals like vivianite.

Hardness
3.5-4
Mohs
Luster
Vitreous
Streak
White
Transparency
Translucent

Is this xenophyllite?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

  • 1
    Test the hardness
    Try to scratch xenophyllite with a known reference. Xenophyllite sits at Mohs 3.5-4, softer than the next harder reference, harder than the previous one.
  • 2
    Check the streak
    Drag the specimen across an unglazed porcelain plate. Xenophyllite leaves a white streak.
  • 3
    Read the luster
    Hold the specimen under a strong light. Xenophyllite typically shows a vitreous luster.
  • 4
    Match the color range
    Compare against the expected color range: bluish green, gray-green.
  • 5
    Look at form & habit
    Crystal system: triclinic. Typical habit: lamellar to platy crystals.

Often confused with

Xenophyllite vs. its common look-alikes, and how to tell them apart in the field.

Often found alongside xenophyllite

Minerals reported to co-occur with xenophyllite. Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula
Na₄Fe₇(PO₄)₆
Mohs hardness
3.5-4
Density
3.55 g/cm³
Streak
White
Luster
Vitreous
Transparency
Translucent
Crystal system
Triclinic
Crystal habit
Lamellar to Platy Crystals
Cleavage
Perfect Basal
Rarity
Rare
Uses
Collector
Host rock
Phosphate-rich Hydrothermal Veins

Where rockhounds find xenophyllite

Classic worldwide localities

  • Wolfsberg, Germany

Field-hunting tip

Look in phosphate-rich hydrothermal veins country, the host setting where xenophyllite typically forms. If you start seeing vivianite, triphylite, strengite in float, you are in the right ground. Field specimens usually show a lamellar to platy crystals habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify xenophyllite?+
Mohs hardness is 3.5-4. It typically shows a vitreous luster. The streak is white. Common colors include bluish green, gray-green.
Where is xenophyllite found?+
Notable localities include Wolfsberg, Germany.
What rocks look like xenophyllite?+
Xenophyllite is most often confused with Vivianite, Triphylite. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with xenophyllite?+
Xenophyllite commonly co-occurs with Vivianite, Triphylite, Strengite. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does xenophyllite form in?+
Xenophyllite typically forms in phosphate-rich hydrothermal veins. Working float back to the host body is the standard way to chase a fresh occurrence.
What is xenophyllite used for?+
Xenophyllite is used in collector.

Find xenophyllite on the map

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