Wonesite is a rare, sodium-rich mica that occurs primarily in metamorphic environments. It typically forms thin, flexible, platy crystals with a distinct pearly luster similar to other members of the mica group.

Hardness

2.5-3

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrareMica Group family

Wonesite

Hardness: 2.5-3
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this wonesite?

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 wonesite with a known reference. Wonesite sits at Mohs 2.5-3, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Streak: white.
3
Read the luster
Hold the specimen under a strong light. Luster: vitreous.
4
Match the color range
Compare against the expected color range: yellow brown, dark brown.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: flakes.

Often confused with

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

mineral

Phlogopite

Mohs 2-3

How to tell apart: Luster reads vitreous on Wonesite and pearly to submetallic on cleavage on Phlogopite.

How to tell apart: Luster reads vitreous on Wonesite and splendent to submetallic, vitreous, pearly on cleavage on Biotite.

Often found alongside wonesite

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

All properties

Chemical formula: (Na,K,□)(Mg,Fe,Al,Fe)₆(Si,Al)₈O₂₀(OH,F)₄
Mohs hardness: 2.5-3
Density: 2.89 g/cm³
Colors: Yellow brown Dark brown
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Monoclinic
Crystal habit: Flakes
Cleavage: {001}, perfect
Rarity: Rare
Uses: Collector, Scientific research
Host rock: In metavolcanics with high Mg:Fe, moderate sodium, and very little calcium, metamorphosed at an estimated 535 ° C

Where rockhounds find wonesite

Classic worldwide localities

Norwich, Windsor Co., Vermont, in the Post Pond Volcanics, southwest corner of the Mt. Cube quadrangle, New Hampshire and Vermont, USA

Field-hunting tip

Where it forms: In metavolcanics with high Mg:Fe, moderate sodium, and very little calcium, metamorphosed at an estimated 535 ° C. If you start seeing phlogopite, talc, anthophyllite in float, you are in the right ground. Typical habit: flakes. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify wonesite?+

Mohs hardness is 2.5-3. Luster: vitreous. The streak is white. Common colors include yellow brown, dark brown.

Where is wonesite found?+

Notable localities include Norwich, Windsor Co., Vermont, in the Post Pond Volcanics, southwest corner of the Mt. Cube quadrangle, New Hampshire and Vermont, USA.

What rocks look like wonesite?+

Wonesite is most often confused with Phlogopite, Biotite, Muscovite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with wonesite?+

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

What kind of rock does wonesite form in?+

Where it forms: In metavolcanics with high Mg:Fe, moderate sodium, and very little calcium, metamorphosed at an estimated 535 ° C. Working float back to the host body is the standard way to chase a fresh occurrence.

What is wonesite used for?+

Wonesite is used in collector, scientific research.

Find wonesite on the map

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