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, so 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, 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.