Pinchite is a rare mercury oxychloride mineral known primarily from the Terlingua mining district in Texas. It typically occurs as small, transparent, yellow-orange tabular crystals associated with other rare mercury minerals in limestone cavities.

Hardness

2-3

Mohs

Luster

Adamantine

Streak

White

Transparency

Transparent

mineralrare

Pinchite

Hardness: 2-3
Luster: Adamantine
Streak: White
Transparency: Transparent

Is this pinchite?

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 pinchite with a known reference. Pinchite sits at Mohs 2-3 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Pinchite leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Pinchite typically shows a adamantine luster.
4
Match the color range
Compare against the expected color range: yellow, yellowish-orange, colorless.
5
Look at form & habit
Crystal system: orthorhombic. Typical habit: tabular crystals, subhedral grains.

Often confused with

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

mineral

Eglestonite

Mohs 2.5

How to tell apart: Streak differs — Pinchite leaves white, Eglestonite leaves yellowish-white.

Often found alongside pinchite

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

All properties

Chemical formula: Hg₅Cl₂O₄
Mohs hardness: 2-3
Density: 7.2 g/cm³
Colors: Yellow Yellowish-orange Colorless
Streak: White
Luster: Adamantine
Transparency: Transparent
Crystal system: Orthorhombic
Crystal habit: Tabular Crystals, Subhedral Grains
Cleavage: None
Rarity: Rare
Uses: Collector
Host rock: Hydrothermal Veins in Limestone
Typical price: $50-500 thumbnail

Where rockhounds find pinchite

Classic worldwide localities

Terlingua, Texas, USA

Field-hunting tip

Look in hydrothermal veins in limestone country — that is the host setting where pinchite typically forms. If you start seeing calcite, cinnabar, terlinguaite in float, you are in the right ground. Field specimens usually show a tabular crystals, subhedral grains habit, so train your eye for that shape before scanning the outcrop.

Common questions

How do you identify pinchite?+

Mohs hardness is 2-3. It typically shows a adamantine luster. The streak is white. Common colors include yellow, yellowish-orange, colorless.

Where is pinchite found?+

Notable localities include Terlingua, Texas, USA.

How much is pinchite worth?+

Typical asking prices fall in the range of $50-500 thumbnail. Quality, size, and provenance can move individual specimens well outside that range.

Is pinchite safe to handle?+

It contains toxic constituents. Contains mercury, which is toxic; wash hands thoroughly after handling specimens and avoid inhaling dust. Handle with care, avoid grinding or breathing dust, and store separately.

What rocks look like pinchite?+

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

What minerals are found with pinchite?+

Pinchite commonly co-occurs with Calcite, Cinnabar, Terlinguaite, Montroydite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does pinchite form in?+

Pinchite typically forms in hydrothermal veins in limestone. Working float back to the host body is the standard way to chase a fresh occurrence.

What is pinchite used for?+

Pinchite is used in collector.

Find pinchite on the map

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