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, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: pale yellowish white.
- 3Read the lusterHold the specimen under a strong light. Luster: silky.
- 4Match the color rangeCompare against the expected color range: white, cream, yellowish brown, pale yellow, canary yellow.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: spherical, tabular.
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, so Meurigite-K leaves pale yellowish white, Kidwellite leaves yellow.
How to tell apart: Streak differs, so Meurigite-K leaves pale yellowish white, Rockbridgeite leaves greenish gray; luster reads silky on Meurigite-K and vitreous to dull on Rockbridgeite.
How to tell apart: Streak differs, so Meurigite-K leaves pale yellowish white, Strengite leaves white; luster reads silky on Meurigite-K and vitreous on Strengite.
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
- [K(H₂O)₂.₅][Fe₈(PO₄)₆(OH)₇]·4H₂O
- Mohs hardness
- 3
- Density
- 2.96 g/cm³
- Streak
- Pale yellowish white
- Luster
- Silky
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Spherical, tabular
- Cleavage
- Good on {001}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Renamed 2007 to meurigite-K because of the approval of meuigite-Na (2007)
Where rockhounds find meurigite-k
Classic worldwide localities
- Santa Rita copper mine at Silver City, New Mexico, USA (type locality)
Field-hunting tip
Where it forms: Renamed 2007 to meurigite-K because of the approval of meuigite-Na (2007). If you start seeing kidwellite, leucophosphite, rockbridgeite in float, you are in the right ground. Typical habit: spherical, tabular. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify meurigite-k?+
Where is meurigite-k found?+
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.
