Marsturite is a rare manganese-bearing silicate mineral primarily found in the metamorphosed ore bodies of the Franklin mining district. It typically occurs as prismatic crystals or fibrous aggregates with a distinct pink to brownish-pink coloration that often appears similar to its associated pyroxenoids, rhodonite and bustamite.
Is this marsturite?
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 marsturite with a known reference. Marsturite sits at Mohs ~6, softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Streak: white.
- 3Read the lusterHold the specimen under a strong light. Luster: frosty, on the tips of crystals.
- 4Match the color rangeCompare against the expected color range: white, light pink.
- 5Look at form & habitCrystal system: triclinic. Typical habit: lath.
Often confused with
Marsturite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Luster reads frosty, on the tips of crystals on Marsturite and vitreous, somewhat pearly on cleavages on Rhodonite.
How to tell apart: Luster reads frosty, on the tips of crystals on Marsturite and vitreous on Bustamite.
Often found alongside marsturite
Minerals reported to co-occur with marsturite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- NaCaMn₃Si₅O₁₄(OH)
- Mohs hardness
- ~6
- Density
- 3.46 g/cm³
- Colors
- Streak
- White
- Luster
- Frosty, on the tips of crystals
- Transparency
- Translucent
- Crystal system
- Triclinic
- Crystal habit
- Lath
- Cleavage
- Imperfect on {100} and {001}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Implanted on manganaxinite and epitaxially overgrown on rhodonite in a metamorphosed stratiform zinc deposit (Franklin, New Jersey, USA)
Where rockhounds find marsturite
Classic worldwide localities
- Franklin, Sussex Co., New Jersey, USA
- Tanohata mine, Iwate Prefecture, Japan
- Molinello manganese mine, near Chiavari, Val Graveglia, Liguria, Italy
Field-hunting tip
Where it forms: Implanted on manganaxinite and epitaxially overgrown on rhodonite in a metamorphosed stratiform zinc deposit (Franklin, New Jersey, USA). If you start seeing rhodonite, manganaxinite, ganophyllite in float, you are in the right ground. Typical habit: lath. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify marsturite?+
Where is marsturite found?+
What rocks look like marsturite?+
What minerals are found with marsturite?+
What kind of rock does marsturite form in?+
What is marsturite used for?+
Find marsturite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
