Mercury is a rare liquid metallic element that occurs naturally as small, spherical, silvery-white droplets within hydrothermal deposits. It is most commonly found associated with cinnabar, which is its primary ore. Due to its toxicity and high density, collectors must handle samples with extreme caution and ensure they are properly encapsulated.

Hardness

Mohs

Luster

Metallic, brilliant

Transparency

Opaque

mineralrare

Mercury

Also: quicksilver, hydrargyrum

Hardness: 0
Luster: Metallic, brilliant
Transparency: Opaque

Is this mercury?

4-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 mercury with a known reference. Mercury sits at Mohs 0, softer than the next harder reference, harder than the previous one.
2
Read the luster
Hold the specimen under a strong light. Luster: metallic, brilliant.
3
Match the color range
Compare against the expected color range: tin white, gray white.
4
Look at form & habit
Crystal system: trigonal. Typical habit: liquid.

Often found alongside mercury

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

All properties

Chemical formula: Hg
Mohs hardness: 0
Density: 13.596 g/cm³
Colors: Tin white Gray white
Luster: Metallic, brilliant
Transparency: Opaque
Crystal system: Trigonal
Crystal habit: Liquid
Cleavage: None
Rarity: Rare
Uses: Scientific instrument, Industrial, Historical specimen
Host rock: In hydrothermal deposits formed at low temperature and associated with hot springs

Where rockhounds find mercury

11 mapped spots

Classic worldwide localities

New Almaden, Santa Clara Co., and Mt. Diablo, Contra Costa Co., California, USA
Terlingua, Brewster Co., Texas, USA
A noted locality at Almadén, Ciudad Real Province, Spain
Mount Avala, near Belgrade, Serbia
Idrija (Idria), Slovenia
Landsberg, near Obermoschel, Rhineland-Palatinate, Germany

Field-hunting tip

Where it forms: In hydrothermal deposits formed at low temperature and associated with hot springs. If you start seeing cinnabar, metacinnabar, calomel in float, you are in the right ground. Typical habit: liquid. Train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in Nevada, Texas. Start trip planning there.

Browse 11 U.S. spots for mercury →

More mercury photos

Common questions

How do you identify mercury?+

Mohs hardness is 0. Luster: metallic, brilliant. Common colors include tin white, gray white.

Where is mercury found?+

Notable localities include New Almaden, Santa Clara Co., and Mt. Diablo, Contra Costa Co., California, USA; Terlingua, Brewster Co., Texas, USA; A noted locality at Almadén, Ciudad Real Province, Spain; Mount Avala, near Belgrade, Serbia; Idrija (Idria), Slovenia.

Can I find mercury in the United States?+

RockHoundR maps 11 mercury rockhounding spots across 2 U.S. states. The top states are Nevada, Texas.

Is mercury safe to handle?+

Mercury contains mercury and calls for real care. Extremely toxic by ingestion, inhalation of vapors, and skin absorption. Must be stored in a sealed, shatterproof container away from heat sources.

What minerals are found with mercury?+

Mercury commonly co-occurs with Cinnabar, Metacinnabar, Calomel, Terlinguaite, Eglestonite, Mercurian silver. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does mercury form in?+

Where it forms: In hydrothermal deposits formed at low temperature and associated with hot springs. Working float back to the host body is the standard way to chase a fresh occurrence.

What is mercury used for?+

Mercury is used in scientific instrument, industrial, historical specimen.

Find mercury on the map

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