Richterite is a member of the sodic-calcic amphibole group, typically appearing as elongated, prismatic or fibrous crystals. It is most frequently found in metamorphosed limestone deposits or alkaline rocks, often exhibiting distinct brown or yellow hues.

Hardness

5-6

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineraluncommonAmphibole Supergroup family

Richterite

Hardness: 5-6
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this richterite?

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 richterite with a known reference. Richterite sits at Mohs 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. Richterite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Richterite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: brown, yellow, red, colorless, green.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: prismatic crystals, fibrous, columnar.

Often confused with

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

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

How to tell apart: Streak differs — Richterite leaves white, Hornblende leaves grayish-white.

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Often found alongside richterite

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

All properties

Chemical formula: Na(NaCa)Mg₅Si₈O₂₂(OH)₂
Mohs hardness: 5-6
Density: 3.0-3.2 g/cm³
Colors: Brown Yellow Red Colorless Green
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Monoclinic
Crystal habit: Prismatic Crystals, Fibrous, Columnar
Cleavage: Perfect Prismatic
Rarity: Uncommon
Uses: Collector
Host rock: Metamorphosed Limestones, Skarns, Alkaline Igneous Rocks
Typical price: $20-150 for thumbnail to cabinet specimens

Where rockhounds find richterite

Classic worldwide localities

Långban, Sweden
Magnet Cove, Arkansas, USA
Quebec, Canada
Khibiny Massif, Russia

Field-hunting tip

Look in metamorphosed limestones, skarns, alkaline igneous rocks country — that is the host setting where richterite typically forms. If you start seeing calcite, dolomite, diopside in float, you are in the right ground. Field specimens usually show a prismatic crystals, fibrous, columnar habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify richterite?+

Mohs hardness is 5-6. It typically shows a vitreous luster. The streak is white. Common colors include brown, yellow, red, colorless.

Where is richterite found?+

Notable localities include Långban, Sweden; Magnet Cove, Arkansas, USA; Quebec, Canada; Khibiny Massif, Russia.

How much is richterite worth?+

Typical asking prices fall in the range of $20-150 for thumbnail to cabinet specimens. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like richterite?+

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

What minerals are found with richterite?+

Richterite commonly co-occurs with Calcite, Dolomite, Diopside, Willemite, Franklinite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does richterite form in?+

Richterite typically forms in metamorphosed limestones, skarns, alkaline igneous rocks. Working float back to the host body is the standard way to chase a fresh occurrence.

What is richterite used for?+

Richterite is used in collector.

Find richterite on the map

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