Joaquinite-(Ce) is a rare silicate mineral primarily known from the world-famous Benitoite Gem Mine in California. It typically forms attractive, honey-colored wedge-shaped crystals perched on white natrolite or associated with deep red neptunite, making it a highly prized specimen for collectors of rare earth minerals.

Hardness

5-5.5

Mohs

Luster

Vitreous

Streak

White

Transparency

Translucent

mineralrareJoaquinite Group family

Joaquinite-(Ce)

Hardness: 5-5.5
Luster: Vitreous
Streak: White
Transparency: Translucent

Is this joaquinite-(ce)?

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 joaquinite-(ce) with a known reference. Joaquinite-(Ce) sits at Mohs 5-5.5 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Joaquinite-(Ce) leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Joaquinite-(Ce) typically shows a vitreous luster.
4
Match the color range
Compare against the expected color range: honey-yellow, brown, orange-brown.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: tabular crystals, wedge-shaped.

Often confused with

Joaquinite-(Ce) vs. its common look-alikes — and how to tell them apart in the field.

mineral

Neptunite

Mohs 5-6

How to tell apart: Streak differs — Joaquinite-(Ce) leaves white, Neptunite leaves brownish red.

Often found alongside joaquinite-(ce)

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

All properties

Chemical formula: NaBa₂Fe²⁺Ce₂Ti₂Si₈O₂₆(OH)·H₂O
Mohs hardness: 5-5.5
Density: 3.8-3.9 g/cm³
Colors: Honey-yellow Brown Orange-brown
Streak: White
Luster: Vitreous
Transparency: Translucent
Crystal system: Monoclinic
Crystal habit: Tabular Crystals, Wedge-shaped
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Glaucophane Schist in Contact with Serpentinite
Typical price: $50-500 thumbnail, $200-2000 cabinet

Where rockhounds find joaquinite-(ce)

Classic worldwide localities

Benitoite Gem Mine, California, USA
San Benito County, California, USA

Field-hunting tip

Look in glaucophane schist in contact with serpentinite country — that is the host setting where joaquinite-(ce) typically forms. If you start seeing benitoite, neptunite, natrolite in float, you are in the right ground. Field specimens usually show a tabular crystals, wedge-shaped habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify joaquinite-(ce)?+

Mohs hardness is 5-5.5. It typically shows a vitreous luster. The streak is white. Common colors include honey-yellow, brown, orange-brown.

Where is joaquinite-(ce) found?+

Notable localities include Benitoite Gem Mine, California, USA; San Benito County, California, USA.

How much is joaquinite-(ce) worth?+

Typical asking prices fall in the range of $50-500 thumbnail, $200-2000 cabinet. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like joaquinite-(ce)?+

Joaquinite-(Ce) is most often confused with Neptunite, Benitoite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with joaquinite-(ce)?+

Joaquinite-(Ce) commonly co-occurs with Benitoite, Neptunite, Natrolite, Serandite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does joaquinite-(ce) form in?+

Joaquinite-(Ce) typically forms in glaucophane schist in contact with serpentinite. Working float back to the host body is the standard way to chase a fresh occurrence.

What is joaquinite-(ce) used for?+

Joaquinite-(Ce) is used in collector.

Find joaquinite-(ce) on the map

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