Romanorlovite is an exceptionally rare mercury-potassium chloride mineral found primarily in volcanic fumaroles. It typically occurs as small, sharp octahedral crystals with a distinct yellow color and high luster, often forming in low-temperature volcanic vent environments.

Hardness

Mohs

Luster

Vitreous

Streak

Yellow

Transparency

Transparent

mineralrare

Romanorlovite

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

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Is this romanorlovite?

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 romanorlovite with a known reference. Romanorlovite 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: yellow-brown, dark brown.
5
Look at form & habit
Crystal system: tetragonal.

Often confused with

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

mineral

Salammoniac

Mohs 1-2

How to tell apart: Romanorlovite is noticeably harder (Mohs ~3 vs. 1-2); streak differs, so Romanorlovite leaves yellow, Salammoniac leaves white.

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Often found alongside romanorlovite

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

All properties

Chemical formula: K₁₁Cu₉Cl₂₅(OH)₄·2H₂O
Mohs hardness: ~3
Density: 2.61 g/cm³
Colors: Yellow-brown Dark brown
Streak: Yellow
Luster: Vitreous
Transparency: Transparent
Crystal system: Tetragonal
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: As sublimates around active fumaroles

Where rockhounds find romanorlovite

Classic worldwide localities

Glavnaya Tenoritovaya and Arsenatnaya fumaroles, Second scoria cone, Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka, Russia

Field-hunting tip

Where it forms: As sublimates around active fumaroles. If you start seeing hematite, pseudobrookite, clinoenstatite in float, you are in the right ground.

Common questions

How do you identify romanorlovite?+

Mohs hardness is ~3. Luster: vitreous. The streak is yellow. Common colors include yellow-brown, dark brown.

Where is romanorlovite found?+

Notable localities include Glavnaya Tenoritovaya and Arsenatnaya fumaroles, Second scoria cone, Northern Breakthrough of the Great Tolbachik Fissure Eruption, Tolbachik volcano, Kamchatka, Russia.

Is romanorlovite safe to handle?+

Romanorlovite contains copper. Contains copper, which is toxic if ingested or inhaled as dust. Wash hands thoroughly after handling and avoid creating dust.

What rocks look like romanorlovite?+

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

What minerals are found with romanorlovite?+

Romanorlovite commonly co-occurs with Hematite, Pseudobrookite, Clinoenstatite, Diopside, Anhydrite, Powellite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does romanorlovite form in?+

Where it forms: As sublimates around active fumaroles. Working float back to the host body is the standard way to chase a fresh occurrence.

What is romanorlovite used for?+

Romanorlovite is used in collector.

Find romanorlovite on the map

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