Hatertite is a rare sodium calcium copper arsenate that forms honey-yellow prismatic tabular crystals. It is a sublimate at a volcanic fumarole. It was first described from North Breach, Great fissure eruption, Tolbachik volcano, Kamchatka Peninsula, Russia.

Hardness

Mohs

Luster

Vitreous

Streak

Yellow

Transparency

Transparent

mineralrare

Hatertite

Hardness: 3
Luster: Vitreous
Streak: Yellow
Transparency: Transparent

No image

Is this hatertite?

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 hatertite with a known reference. Hatertite 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: yellow.
3
Read the luster
Hold the specimen under a strong light. Luster: vitreous.
4
Match the color range
Compare against the expected color range: honey-yellow.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: prismatic tabular crystals.

Often confused with

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

mineral

Vanthoffite

Mohs 3.5

How to tell apart: Streak differs, so Hatertite leaves yellow, Vanthoffite leaves white.

How to tell apart: Streak differs, so Hatertite leaves yellow, Thénardite leaves white.

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Often found alongside hatertite

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

All properties

Chemical formula: NaNaCa(Cu²⁺Fe³⁺)(AsO₄)₃
Mohs hardness: 3
Density: 4.060 g/cm³
Colors: Honey-yellow
Streak: Yellow
Luster: Vitreous
Transparency: Transparent
Crystal system: Monoclinic
Crystal habit: Prismatic tabular crystals
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: A sublimate at a volcanic fumarole

Where rockhounds find hatertite

Classic worldwide localities

North Breach, Great fissure eruption, Tolbachik volcano, Kamchatka Peninsula, Russia

Field-hunting tip

Where it forms: A sublimate at a volcanic fumarole. If you start seeing ponomarevite, piypite, dolerophanite in float, you are in the right ground. Typical habit: prismatic tabular crystals. Train your eye for that shape before scanning the outcrop.

Common questions

How do you identify hatertite?+

Mohs hardness is 3. Luster: vitreous. The streak is yellow. Common colors include honey-yellow.

Where is hatertite found?+

Notable localities include North Breach, Great fissure eruption, Tolbachik volcano, Kamchatka Peninsula, Russia.

Is hatertite safe to handle?+

Hatertite contains arsenic and copper and calls for real care. Contains arsenic, which is toxic if ingested or inhaled as dust. Wash hands thoroughly after handling and avoid creating dust.

What rocks look like hatertite?+

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

What minerals are found with hatertite?+

Hatertite commonly co-occurs with Ponomarevite, Piypite, Dolerophanite, Euchlorine, Sylvite, Lammerite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does hatertite form in?+

Where it forms: A sublimate at a volcanic fumarole. Working float back to the host body is the standard way to chase a fresh occurrence.

What is hatertite used for?+

Hatertite is used in collector.

Find hatertite on the map

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