Loseyite is a very rare carbonate mineral almost exclusively found in the Franklin mining district of New Jersey. It is characterized by its delicate, bladed white to light blue crystals that often form radiating clusters on a matrix of other zinc-rich minerals.
Is this loseyite?
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 loseyite with a known reference. Loseyite 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. Loseyite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Loseyite typically shows a pearly luster.
- 4Match the color rangeCompare against the expected color range: white, colorless, light blue.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: bladed crystals, radial aggregates.
Often confused with
Loseyite vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside loseyite
Minerals reported to co-occur with loseyite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (Mn,Zn)₇(CO₃)₂(OH)₁₀
- Mohs hardness
- 3
- Density
- 3.28 g/cm³
- Colors
- Streak
- White
- Luster
- Pearly
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Bladed Crystals, Radial Aggregates
- Cleavage
- Perfect On {010}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Hydrothermal Vein Deposits in Zinc-manganese Orebodies
- Typical price
- $50-500 depending on specimen size and quality
Where rockhounds find loseyite
Classic worldwide localities
- Franklin Mining District, New Jersey, USA
Field-hunting tip
Look in hydrothermal vein deposits in zinc-manganese orebodies country — that is the host setting where loseyite typically forms. If you start seeing hodgkinsonite, franklinite, willemite in float, you are in the right ground. Field specimens usually show a bladed crystals, radial aggregates habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify loseyite?+
Where is loseyite found?+
How much is loseyite worth?+
What rocks look like loseyite?+
What minerals are found with loseyite?+
What kind of rock does loseyite form in?+
What is loseyite used for?+
Find loseyite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
