Anthophyllite is a magnesium-rich amphibole typically found in regionally metamorphosed rocks. It is easily identified by its characteristic clove-brown to grayish color and its fibrous or lamellar habit, though it should be handled with extreme caution due to its asbestiform nature.

Hardness

5.5-6

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralcommonAmphibole Supergroup family

Anthophyllite

Hardness: 5.5-6
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this anthophyllite?

5-step field check

Run through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.

1
Test the hardness
Try to scratch anthophyllite with a known reference. Anthophyllite sits at Mohs 5.5-6, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Anthophyllite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Anthophyllite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: brown, gray, white, greenish.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: fibrous, columnar, or lamellar.

Often confused with

Anthophyllite vs. its common look-alikes, and how to tell them apart in the field.

How to tell apart: Luster reads vitreous on Anthophyllite and vitreous to silky on Actinolite.

Often found alongside anthophyllite

Minerals reported to co-occur with anthophyllite. Spotting these in float or country rock is a strong cue you are in the right ground.

All properties

Chemical formula: Mg₂Mg₅Si₈O₂₂(OH)₂
Mohs hardness: 5.5-6
Density: 2.8-3.5 g/cm³
Colors: Brown Gray White Greenish
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Orthorhombic
Crystal habit: Fibrous, Columnar, Or Lamellar
Cleavage: Perfect in Two Directions
Rarity: Common
Uses: Collector, Geological Study
Host rock: Metamorphic Rocks Like Schist and Gneiss
Typical price: $10-50 per specimen

Where rockhounds find anthophyllite

2 mapped spots

Classic worldwide localities

Kongsberg, Norway
Amity, New York, USA
Finland
Greenland

Field-hunting tip

Look in metamorphic rocks like schist and gneiss country, the host setting where anthophyllite typically forms. If you start seeing garnet, cordierite, talc in float, you are in the right ground. Field specimens usually show a fibrous, columnar, or lamellar habit, so train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in California, New York. Start trip planning there.

Browse 2 U.S. spots for anthophyllite →

Common questions

How do you identify anthophyllite?+

Mohs hardness is 5.5-6. It typically shows a vitreous luster. The streak is white. Common colors include brown, gray, white, greenish.

Where is anthophyllite found?+

Notable localities include Kongsberg, Norway; Amity, New York, USA; Finland; Greenland.

Can I find anthophyllite in the United States?+

RockHoundR maps 2 anthophyllite rockhounding spots across 2 U.S. states. The top states are California, New York.

How much is anthophyllite worth?+

Typical asking prices fall in the range of $10-50 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

Is anthophyllite safe to handle?+

It contains toxic constituents. Anthophyllite is a member of the asbestos group of minerals; inhaling airborne fibers can cause severe lung diseases, including asbestosis and mesothelioma. Handle with care and avoid generating dust or cutting specimens. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like anthophyllite?+

Anthophyllite is most often confused with Tremolite, Actinolite, Cummingtonite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with anthophyllite?+

Anthophyllite commonly co-occurs with Garnet, Cordierite, Talc, Olivine. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does anthophyllite form in?+

Anthophyllite typically forms in metamorphic rocks like schist and gneiss. Working float back to the host body is the standard way to chase a fresh occurrence.

What is anthophyllite used for?+

Anthophyllite is used in collector, geological study.

Find anthophyllite on the map

RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.