Niksergievite is a rare phyllosilicate mineral belonging to the clintonite group, typically found as small, pearly-lustered lamellar crystals or scaly masses. It is primarily known from the Khaidarkan mercury-antimony deposit in Kyrgyzstan where it forms as a rare alteration product. Collectors should look for its characteristic mica-like habit and association with fluorite in hydrothermal vein environments.

Hardness

3.5

Mohs

Luster

Pearly

Streak

White

Transparency

Translucent

mineralrareClintonite Group family

Niksergievite

Hardness: 3.5
Luster: Pearly
Streak: White
Transparency: Translucent

No image

Is this niksergievite?

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 niksergievite with a known reference. Niksergievite sits at Mohs 3.5, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Niksergievite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Niksergievite typically shows a pearly luster.
4
Match the color range
Compare against the expected color range: yellow, brown, white.
5
Look at form & habit
Crystal system: monoclinic. Typical habit: lamellar crystals, scaly aggregates.

Often confused with

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

Often found alongside niksergievite

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

All properties

Chemical formula: (□,Ca,Na)₂(Al,Mg,Fe)₃(Al,Si)₄O₁₀(OH)₂
Mohs hardness: 3.5
Density: 3.08 g/cm³
Colors: Yellow Brown White
Streak: White
Luster: Pearly
Transparency: Translucent
Crystal system: Monoclinic
Crystal habit: Lamellar Crystals, Scaly Aggregates
Cleavage: Perfect Basal
Rarity: Rare
Uses: Collector
Host rock: Hydrothermal Vein Deposits in Sedimentary Rocks
Typical price: $50-300 per specimen

Where rockhounds find niksergievite

Classic worldwide localities

Khaidarkan, Kyrgyzstan

Field-hunting tip

Look in hydrothermal vein deposits in sedimentary rocks country, the host setting where niksergievite typically forms. If you start seeing fluorite, quartz, calcite in float, you are in the right ground. Field specimens usually show a lamellar crystals, scaly aggregates habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify niksergievite?+

Mohs hardness is 3.5. It typically shows a pearly luster. The streak is white. Common colors include yellow, brown, white.

Where is niksergievite found?+

Notable localities include Khaidarkan, Kyrgyzstan.

How much is niksergievite worth?+

Typical asking prices fall in the range of $50-300 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like niksergievite?+

Niksergievite is most often confused with Clintonite, Margarite, Phlogopite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with niksergievite?+

Niksergievite commonly co-occurs with Fluorite, Quartz, Calcite, Stibnite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does niksergievite form in?+

Niksergievite typically forms in hydrothermal vein deposits in sedimentary rocks. Working float back to the host body is the standard way to chase a fresh occurrence.

What is niksergievite used for?+

Niksergievite is used in collector.

Find niksergievite on the map

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