Cuatrocapaite-(K) is an extremely rare sulfate mineral discovered in evaporitic environments in Mexico. It is typically found as fragile, pale yellow platy crystals or foliated masses associated with gypsum and other evaporite minerals. Due to its scarcity and delicate nature, it is highly sought after by systematic mineral collectors.

Hardness

Mohs

Luster

Pearly

Streak

White

Transparency

Translucent

mineralrareCuatrocapaite family

Cuatrocapaite-(K)

Hardness: 2
Luster: Pearly
Streak: White
Transparency: Translucent

No image

Is this cuatrocapaite-(k)?

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 cuatrocapaite-(k) with a known reference. Cuatrocapaite-(K) sits at Mohs 2 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Cuatrocapaite-(K) leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Cuatrocapaite-(K) typically shows a pearly luster.
4
Match the color range
Compare against the expected color range: yellow, pale yellow.
5
Look at form & habit
Crystal system: trigonal. Typical habit: platy crystals, pseudohexagonal, foliated aggregates.

Often confused with

Cuatrocapaite-(K) vs. its common look-alikes — and how to tell them apart in the field.

Often found alongside cuatrocapaite-(k)

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

All properties

Chemical formula: K₂Na₃(H₂O)₁₀[Ce₂(SO₄)₄(OH)₂]·nH₂O
Mohs hardness: 2
Density: 2.7 g/cm³
Colors: Yellow Pale Yellow
Streak: White
Luster: Pearly
Transparency: Translucent
Crystal system: Trigonal
Crystal habit: Platy Crystals, Pseudohexagonal, Foliated Aggregates
Cleavage: Perfect Basal
Rarity: Rare
Uses: Collector
Host rock: Evaporitic Deposits
Typical price: $50-300+ per specimen depending on size and rarity

Where rockhounds find cuatrocapaite-(k)

Classic worldwide localities

Cuatro Ciénegas, Coahuila, Mexico

Field-hunting tip

Look in evaporitic deposits country — that is the host setting where cuatrocapaite-(k) typically forms. If you start seeing gypsum, anhydrite, halite in float, you are in the right ground. Field specimens usually show a platy crystals, pseudohexagonal, foliated aggregates habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify cuatrocapaite-(k)?+

Mohs hardness is 2. It typically shows a pearly luster. The streak is white. Common colors include yellow, pale yellow.

Where is cuatrocapaite-(k) found?+

Notable localities include Cuatro Ciénegas, Coahuila, Mexico.

How much is cuatrocapaite-(k) worth?+

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

What rocks look like cuatrocapaite-(k)?+

Cuatrocapaite-(K) is most often confused with Molybdomenite. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with cuatrocapaite-(k)?+

Cuatrocapaite-(K) commonly co-occurs with Gypsum, Anhydrite, Halite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does cuatrocapaite-(k) form in?+

Cuatrocapaite-(K) typically forms in evaporitic deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is cuatrocapaite-(k) used for?+

Cuatrocapaite-(K) is used in collector.

Find cuatrocapaite-(k) on the map

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