Meurigite-K is a rare hydrated potassium iron phosphate that typically forms as delicate, radiating clusters of acicular crystals. It is most easily identified by its distinctive yellow-to-brown color and its common occurrence as a secondary mineral in oxidized iron-phosphate deposits. Because of its scarcity and small crystal size, it is a highly sought-after species for micromount collectors.
Is this meurigite-k?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch meurigite-k with a known reference. Meurigite-K sits at Mohs 3-4 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Meurigite-K leaves a yellowish-white streak.
- 3Read the lusterHold the specimen under a strong light. Meurigite-K typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: yellow, yellow-brown, brownish-orange.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: radiating sprays of acicular crystals, fibrous crusts, spherical aggregates.
Often confused with
Meurigite-K vs. its common look-alikes — and how to tell them apart in the field.
How to tell apart: Streak differs — Meurigite-K leaves yellowish-white, Rockbridgeite leaves greenish-brown.
How to tell apart: Streak differs — Meurigite-K leaves yellowish-white, Strengite leaves white.
Often found alongside meurigite-k
Minerals reported to co-occur with meurigite-k. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- KFe₇(PO₄)₄(OH)₉·8H₂O
- Mohs hardness
- 3-4
- Density
- 2.84 g/cm³
- Streak
- Yellowish-white
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Radiating Sprays of Acicular Crystals, Fibrous Crusts, Spherical Aggregates
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Phosphate-rich Hydrothermal Veins in Oxidized Ore Deposits
- Typical price
- $50-300 per specimen
Where rockhounds find meurigite-k
Classic worldwide localities
- Cwmystwyth mine, Wales
- Hagendorf, Germany
- Piraí, Brazil
Field-hunting tip
Look in phosphate-rich hydrothermal veins in oxidized ore deposits country — that is the host setting where meurigite-k typically forms. If you start seeing kidwellite, leucophosphite, rockbridgeite in float, you are in the right ground. Field specimens usually show a radiating sprays of acicular crystals, fibrous crusts, spherical aggregates habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify meurigite-k?+
Where is meurigite-k found?+
How much is meurigite-k worth?+
What rocks look like meurigite-k?+
What minerals are found with meurigite-k?+
What kind of rock does meurigite-k form in?+
What is meurigite-k used for?+
Find meurigite-k on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
