Caswellsilverite is an extremely rare sulfide mineral found almost exclusively in enstatite achondrite meteorites. It typically occurs as microscopic inclusions or small anhedral grains associated with other sulfides and pyroxenes. Due to its extraterrestrial origin and scarcity, it is highly sought after by meteorite collectors.

Hardness

3.5

Mohs

Luster

Metallic

Streak

Black

Transparency

Opaque

mineralrare

Caswellsilverite

Hardness: 3.5
Luster: Metallic
Streak: Black
Transparency: Opaque

Is this caswellsilverite?

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 caswellsilverite with a known reference. Caswellsilverite sits at Mohs 3.5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Caswellsilverite leaves a black streak.
3
Read the luster
Hold the specimen under a strong light. Caswellsilverite typically shows a metallic luster.
4
Match the color range
Compare against the expected color range: black, gray.
5
Look at form & habit
Crystal system: trigonal. Typical habit: anhedral grains.

Often confused with

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

Often found alongside caswellsilverite

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

All properties

Chemical formula: NaCrS₂
Mohs hardness: 3.5
Density: 4.49 g/cm³
Colors: Black Gray
Streak: Black
Luster: Metallic
Transparency: Opaque
Crystal system: Trigonal
Crystal habit: Anhedral Grains
Cleavage: Perfect
Rarity: Rare
Uses: Collector
Host rock: Enstatite Achondrite Meteorites
Typical price: $500+ per specimen

Where rockhounds find caswellsilverite

Classic worldwide localities

Norton County meteorite, Kansas, USA

Field-hunting tip

Look in enstatite achondrite meteorites country — that is the host setting where caswellsilverite typically forms. If you start seeing enstatite, diopside, troilite in float, you are in the right ground. Field specimens usually show a anhedral grains habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify caswellsilverite?+

Mohs hardness is 3.5. It typically shows a metallic luster. The streak is black. Common colors include black, gray.

Where is caswellsilverite found?+

Notable localities include Norton County meteorite, Kansas, USA.

How much is caswellsilverite worth?+

Typical asking prices fall in the range of $500+ per specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like caswellsilverite?+

Caswellsilverite is most often confused with Troilite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with caswellsilverite?+

Caswellsilverite commonly co-occurs with enstatite, diopside, troilite, oldhamite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does caswellsilverite form in?+

Caswellsilverite typically forms in enstatite achondrite meteorites. Working float back to the host body is the standard way to chase a fresh occurrence.

What is caswellsilverite used for?+

Caswellsilverite is used in collector.

Find caswellsilverite on the map

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