Carlosturanite is a rare, fibrous magnesium silicate mineral typically found as asbestiform aggregates within serpentinized ultramafic rocks. It is most notable for its striking silky luster and its discovery in the alpine metamorphic terranes of northern Italy. Collectors should handle specimens carefully due to their fibrous, asbestos-like nature.
Is this carlosturanite?
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 carlosturanite with a known reference. Carlosturanite sits at Mohs 2.5 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Carlosturanite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Carlosturanite typically shows a silky luster.
- 4Match the color rangeCompare against the expected color range: brown, greenish-brown, black.
- 5Look at form & habitCrystal system: monoclinic. Typical habit: fibrous, asbestiform.
Often confused with
Carlosturanite vs. its common look-alikes — and how to tell them apart in the field.
How to tell apart: Luster reads silky on Carlosturanite and greasy on Antigorite.
How to tell apart: Tremolite is the harder of the two (Mohs 5-6 vs. 2.5); luster reads silky on Carlosturanite and vitreous on Tremolite.
Often found alongside carlosturanite
Minerals reported to co-occur with carlosturanite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Chemical formula
- (Mg,Fe,Ti)₂₁Si₁₂O₂₈(OH)₃₄
- Mohs hardness
- 2.5
- Density
- 2.68 g/cm³
- Colors
- Streak
- White
- Luster
- Silky
- Transparency
- Opaque
- Crystal system
- Monoclinic
- Crystal habit
- Fibrous, Asbestiform
- Cleavage
- Perfect
- Rarity
- Rare
- Uses
- Collector
- Host rock
- Metamorphic Rocks, Specifically Serpentinites
- Typical price
- $50-300 per specimen
Where rockhounds find carlosturanite
Classic worldwide localities
- Val Malenco, Italy
- Lanzo Valley, Italy
Field-hunting tip
Look in metamorphic rocks, specifically serpentinites country — that is the host setting where carlosturanite typically forms. If you start seeing diopside, olivine, magnetite in float, you are in the right ground. Field specimens usually show a fibrous, asbestiform habit, so train your eye for that shape before scanning the outcrop.
Common questions
How do you identify carlosturanite?+
Where is carlosturanite found?+
How much is carlosturanite worth?+
Is carlosturanite safe to handle?+
What rocks look like carlosturanite?+
What minerals are found with carlosturanite?+
What kind of rock does carlosturanite form in?+
What is carlosturanite used for?+
Find carlosturanite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
