Johninnesite is a rare manganese magnesium silicate mineral known primarily from the zinc deposits of Franklin and Sterling Hill. Collectors typically look for its characteristic pink to brownish-pink fibrous or needle-like crystals often found growing in association with other rare fluorescent Franklin minerals.
Is this johninnesite?
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 johninnesite with a known reference. Johninnesite sits at Mohs 4 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Johninnesite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Johninnesite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: pink, brownish pink.
- 5Look at form & habitCrystal system: triclinic. Typical habit: fibrous, acicular, prismatic crystals, radiating clusters.
Often confused with
Johninnesite vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside johninnesite
Minerals reported to co-occur with johninnesite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Na₂Mn₇Mg₂Si₁₂As₂O₃₆(OH)₆
- Mohs hardness
- 4
- Density
- 3.55 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Triclinic
- Crystal habit
- Fibrous, Acicular, Prismatic Crystals, Radiating Clusters
- Cleavage
- Good On {100}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Metamorphosed Zinc Ore Bodies
- Typical price
- $100-500 thumbnail, $500+ specimen
Where rockhounds find johninnesite
Classic worldwide localities
- Franklin Mine, New Jersey, USA
- Sterling Hill Mine, New Jersey, USA
Field-hunting tip
Look in metamorphosed zinc ore bodies country — that is the host setting where johninnesite typically forms. If you start seeing willemite, franklinite, zincite in float, you are in the right ground. Field specimens usually show a fibrous, acicular, prismatic crystals, radiating clusters habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify johninnesite?+
Where is johninnesite found?+
How much is johninnesite worth?+
Is johninnesite safe to handle?+
What rocks look like johninnesite?+
What minerals are found with johninnesite?+
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Find johninnesite on the map
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