Clinohedrite is a prized fluorescent mineral best known from the Franklin-Sterling Hill mining district. It typically forms prismatic crystals or radial sprays that exhibit a characteristic, vivid orange fluorescence under shortwave ultraviolet light.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrare

Clinohedrite

Hardness: 5
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this clinohedrite?

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 clinohedrite with a known reference. Clinohedrite sits at Mohs 5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Clinohedrite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Clinohedrite typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: colorless, white, yellow, pink, green.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: prismatic crystals, radial aggregates, massive.

Often confused with

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

Often found alongside clinohedrite

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

All properties

Chemical formula: CaZn(SiO₄)·H₂O
Mohs hardness: 5
Density: 3.3 g/cm³
Colors: Colorless White Yellow Pink Green
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Monoclinic
Crystal habit: Prismatic Crystals, Radial Aggregates, Massive
Cleavage: Perfect On {010}
Fluorescence: Bright Orange Under SW UV
Rarity: Rare
Uses: Collector
Host rock: Metamorphosed Zinc Ore Deposits
Typical price: $20-150 thumbnail, $200+ cabinet specimen

Where rockhounds find clinohedrite

Classic worldwide localities

Franklin, New Jersey, USA
Sterling Hill, New Jersey, USA
Tsumeb, Namibia

Field-hunting tip

Look in metamorphosed zinc ore deposits country, the host setting where clinohedrite typically forms. If you start seeing willemite, franklinite, hardystonite in float, you are in the right ground. Field specimens usually show a prismatic crystals, radial aggregates, massive habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify clinohedrite?+

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

Where is clinohedrite found?+

Notable localities include Franklin, New Jersey, USA; Sterling Hill, New Jersey, USA; Tsumeb, Namibia.

How much is clinohedrite worth?+

Typical asking prices fall in the range of $20-150 thumbnail, $200+ cabinet specimen. Quality, size, and provenance can move individual specimens well outside that range.

Is clinohedrite safe to handle?+

It contains toxic constituents. Contains zinc, wash hands after handling specimens, especially if powdering occurs. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like clinohedrite?+

Clinohedrite is most often confused with Hemimorphite, Willemite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with clinohedrite?+

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

What kind of rock does clinohedrite form in?+

Clinohedrite typically forms in metamorphosed zinc ore deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is clinohedrite used for?+

Clinohedrite is used in collector.

Find clinohedrite on the map

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