Tatarinovite is a rare calcium aluminum sulfate that forms colorless dipyramidal {10 4} crystals. Associated minerals include diopside, xonotlite and clinochlore. It was first described from Bazhenovskoe chrysotile deposit, near Asbest, Middle Urals, Russia.

Hardness

Mohs

Luster

Vitreous

Streak

White

Transparency

Transparent

mineralrareEttringite Group family

Tatarinovite

Hardness: ~3
Luster: Vitreous
Streak: White
Transparency: Transparent

Is this tatarinovite?

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 tatarinovite with a known reference. Tatarinovite sits at Mohs ~3, 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
Read the luster
Hold the specimen under a strong light. Luster: vitreous.
4
Match the color range
Compare against the expected color range: colorless.
5
Look at form & habit
Crystal system: hexagonal. Typical habit: dipyramidal {10 4} crystals.

Often confused with

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

Often found alongside tatarinovite

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

All properties

Chemical formula: Ca₃Al(SO₄)[B(OH)₄](OH)₆·12H₂O
Mohs hardness: ~3
Density: 1.79 g/cm³
Colors: Colorless
Streak: White
Luster: Vitreous
Transparency: Transparent
Crystal system: Hexagonal
Crystal habit: Dipyramidal {10 4} crystals
Cleavage: Perfect on {100}
Rarity: Rare
Uses: Collector
Host rock: In cavities in a rodingite body at the contact between a dike of partly rodingitized gabbroic rock and hosting serpentinite

Where rockhounds find tatarinovite

Classic worldwide localities

Bazhenovskoe chrysotile deposit, near Asbest, Middle Urals, Russia

Field-hunting tip

Where it forms: In cavities in a rodingite body at the contact between a dike of partly rodingitized gabbroic rock and hosting serpentinite. If you start seeing diopside, xonotlite, clinochlore in float, you are in the right ground. Typical habit: dipyramidal {10 4} crystals. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify tatarinovite?+

Mohs hardness is ~3. Luster: vitreous. The streak is white. Common colors include colorless.

Where is tatarinovite found?+

Notable localities include Bazhenovskoe chrysotile deposit, near Asbest, Middle Urals, Russia.

What rocks look like tatarinovite?+

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

What minerals are found with tatarinovite?+

Tatarinovite commonly co-occurs with Diopside, Xonotlite, Clinochlore, Pectolite, Calcite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does tatarinovite form in?+

Where it forms: In cavities in a rodingite body at the contact between a dike of partly rodingitized gabbroic rock and hosting serpentinite. Working float back to the host body is the standard way to chase a fresh occurrence.

What is tatarinovite used for?+

Tatarinovite is used in collector.

Find tatarinovite on the map

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