Reppiaite is an extremely rare manganese vanadate mineral first discovered in the manganese mines of the Val Graveglia district in Italy. It typically appears as small, dark reddish-brown tabular crystals embedded within manganese-bearing host rocks. Collectors prize it for its unique chemical composition and restricted locality occurrences.
Is this reppiaite?
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 reppiaite with a known reference. Reppiaite 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: yellow-orange.
- 3Read the lusterHold the specimen under a strong light. Luster: vitreous.
- 4Match the color rangeCompare against the expected color range: orange red.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: tabular crystals, platy aggregates.
Often confused with
Reppiaite vs. its common look-alikes, and how to tell them apart in the field.
How to tell apart: Streak differs, so Reppiaite leaves yellow-orange, Fernandinite leaves dark green; luster reads vitreous on Reppiaite and submetallic on Fernandinite.
How to tell apart: Braunite is the harder of the two (Mohs 6-6.5 vs. ~3); streak differs, so Reppiaite leaves yellow-orange, Braunite leaves brownish black to steel-gray; luster reads vitreous on Reppiaite and submetallic on Braunite.
Often found alongside reppiaite
Minerals reported to co-occur with reppiaite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- Mn²⁺₅(VO₄)₂(OH)₄
- Mohs hardness
- ~3
- Density
- 3.92 g/cm³
- Colors
- Streak
- Yellow-orange
- Luster
- Vitreous
- Transparency
- Transparent
- Crystal system
- Monoclinic
- Crystal habit
- Tabular crystals, platy aggregates
- Cleavage
- Perfect on {001}
- Rarity
- Rare
- Uses
- Collector
- Host rock
- A rare mineral, deposited from V–As-bearing hydrothermal solutions in fractures cutting manganiferous cherts
Where rockhounds find reppiaite
Classic worldwide localities
- Gambatesa mine, near Reppia, Val Graveglia, Liguria, Italy
Field-hunting tip
Where it forms: A rare mineral, deposited from V–As-bearing hydrothermal solutions in fractures cutting manganiferous cherts. If you start seeing hausmannite, tephroite, mn–ca carbonates in float, you are in the right ground. Typical habit: tabular crystals, platy aggregates. Train your eye for that shape before scanning the outcrop.
Common questions
How do you identify reppiaite?+
Where is reppiaite found?+
Is reppiaite safe to handle?+
What rocks look like reppiaite?+
What minerals are found with reppiaite?+
What kind of rock does reppiaite form in?+
What is reppiaite used for?+
Find reppiaite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
