Cortesognoite is a rare calcium-vanadium silicate mineral discovered in the manganese deposits of the Molinello mine in Liguria, Italy. It typically occurs as small, brownish anhedral grains embedded within metamorphic rock matrices alongside other manganese-bearing species.
Is this cortesognoite?
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 cortesognoite with a known reference. Cortesognoite sits at Mohs 5.5-6 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Cortesognoite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Cortesognoite typically shows a vitreous luster.
- 4Match the color rangeCompare against the expected color range: yellowish-brown, brown.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: anhedral grains and aggregates.
Often confused with
Cortesognoite vs. its common look-alikes — and how to tell them apart in the field.
Often found alongside cortesognoite
Minerals reported to co-occur with cortesognoite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- CaV₂SiO₇
- Mohs hardness
- 5.5-6
- Density
- 3.55 g/cm³
- Colors
- Streak
- White
- Luster
- Vitreous
- Transparency
- Translucent
- Crystal system
- Monoclinic
- Crystal habit
- Anhedral Grains and Aggregates
- Cleavage
- None
- Rarity
- Rare
- Uses
- Collector, Scientific Research
- Host rock
- Manganese-rich Metamorphic Rocks
- Typical price
- n/a - highly rare
Where rockhounds find cortesognoite
Classic worldwide localities
- Molinello Mine, Italy
Field-hunting tip
Look in manganese-rich metamorphic rocks country — that is the host setting where cortesognoite typically forms. If you start seeing quartz, calcite, braunite in float, you are in the right ground. Field specimens usually show a anhedral grains and aggregates habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify cortesognoite?+
Where is cortesognoite found?+
How much is cortesognoite worth?+
What rocks look like cortesognoite?+
What minerals are found with cortesognoite?+
What kind of rock does cortesognoite form in?+
What is cortesognoite used for?+
Find cortesognoite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
