Strontio-orthojoaquinite is an extremely rare member of the joaquinite group found almost exclusively in the unique geologic environment of the Dallas Gem Mine in California. It typically occurs as tiny, honey-colored tabular crystals associated with benitoite and natrolite in serpentinite veins. Collectors value it for its limited distribution and complex crystal structure.

Hardness

5-5.5

Mohs

Streak

White

Transparency

Transparent

mineralrareJoaquinite Group family

Strontio-orthojoaquinite

Hardness: 5-5.5
Streak: White
Transparency: Transparent

Is this strontio-orthojoaquinite?

4-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 strontio-orthojoaquinite with a known reference. Strontio-orthojoaquinite 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. Streak: white.
3
Match the color range
Compare against the expected color range: green, yellow green.
4
Look at form & habit
Crystal system: orthorhombic. Typical habit: tabular crystals, pseudo-hexagonal prisms.

Often confused with

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

No image

mineral

Bario-orthojoaquinite

Mohs 5.5

How to tell apart: Streak differs, so Strontio-orthojoaquinite leaves white, Bario-orthojoaquinite leaves pale yellow.

Compare →

Often found alongside strontio-orthojoaquinite

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

All properties

Chemical formula: NaSr₄FeTi₂Si₈O₂₄(OH)₄
Mohs hardness: 5-5.5
Density: 3.62 g/cm³
Colors: Green Yellow green
Streak: White
Transparency: Transparent
Crystal system: Orthorhombic
Crystal habit: Tabular crystals, pseudo-hexagonal prisms
Cleavage: Perfect on {001}
Rarity: Rare
Uses: Collector
Host rock: In an amphibole-albitite block embedded in serpentinite

Where rockhounds find strontio-orthojoaquinite

Classic worldwide localities

Ohmi region, Niigata prefecture, Japan

Field-hunting tip

Where it forms: In an amphibole-albitite block embedded in serpentinite. If you start seeing benitoite, leucosphenite, ohmilite in float, you are in the right ground. Typical habit: tabular crystals, pseudo-hexagonal prisms. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify strontio-orthojoaquinite?+

Mohs hardness is 5-5.5. The streak is white. Common colors include green, yellow green.

Where is strontio-orthojoaquinite found?+

Notable localities include Ohmi region, Niigata prefecture, Japan.

What rocks look like strontio-orthojoaquinite?+

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

What minerals are found with strontio-orthojoaquinite?+

Strontio-orthojoaquinite commonly co-occurs with Benitoite, Leucosphenite, Ohmilite, Sr-apatite, Albite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does strontio-orthojoaquinite form in?+

Where it forms: In an amphibole-albitite block embedded in serpentinite. Working float back to the host body is the standard way to chase a fresh occurrence.

What is strontio-orthojoaquinite used for?+

Strontio-orthojoaquinite is used in collector.

Find strontio-orthojoaquinite on the map

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