Cerargyrite, commonly known as horn silver, is a secondary silver mineral found in the oxidized zones of silver deposits. It is notable for its soft, waxy, or horn-like appearance and its tendency to darken when exposed to light.

Hardness
1.5
Mohs
Luster
Resinous
Streak
White
Transparency
Translucent

Is this cerargyrite?

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 cerargyrite with a known reference. Cerargyrite sits at Mohs 1.5 — softer than the next harder reference, harder than the previous one.
  • 2
    Check the streak
    Drag the specimen across an unglazed porcelain plate. Cerargyrite leaves a white streak.
  • 3
    Read the luster
    Hold the specimen under a strong light. Cerargyrite typically shows a resinous luster.
  • 4
    Match the color range
    Compare against the expected color range: colorless, white, gray, yellowish, brownish, violet.
  • 5
    Look at form & habit
    Crystal system: cubic. Typical habit: massive, encrusting, cubic crystals.

Often confused with

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

Often found alongside cerargyrite

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

All properties

Chemical formula
AgCl
Mohs hardness
1.5
Density
5.55 g/cm³
Streak
White
Luster
Resinous
Transparency
Translucent
Crystal system
Cubic
Crystal habit
Massive, Encrusting, Cubic Crystals
Cleavage
None
Rarity
Uncommon
Uses
Collector, Ore of Silver
Host rock
Oxidized Zones of Silver Ore Deposits
Typical price
$20-150 for thumbnail to small cabinet specimens

Where rockhounds find cerargyrite

3 mapped spots

Classic worldwide localities

  • Broken Hill, Australia
  • Chañarcillo, Chile
  • Guanajuato, Mexico
  • Leadville, Colorado, USA
  • Tsumeb, Namibia

Field-hunting tip

Look in oxidized zones of silver ore deposits country — that is the host setting where cerargyrite typically forms. If you start seeing silver, iodargyrite, bromargyrite in float, you are in the right ground. Field specimens usually show a massive, encrusting, cubic crystals habit, so train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in New Mexico, Texas — start trip planning there.

Common questions

How do you identify cerargyrite?+
Mohs hardness is 1.5. It typically shows a resinous luster. The streak is white. Common colors include colorless, white, gray, yellowish.
Where is cerargyrite found?+
Notable localities include Broken Hill, Australia; Chañarcillo, Chile; Guanajuato, Mexico; Leadville, Colorado, USA; Tsumeb, Namibia.
Can I find cerargyrite in the United States?+
RockHoundR maps 3 cerargyrite rockhounding spots across 2 U.S. states — the top states are New Mexico, Texas.
How much is cerargyrite worth?+
Typical asking prices fall in the range of $20-150 for thumbnail to small cabinet specimens. Quality, size, and provenance can move individual specimens well outside that range.
Is cerargyrite safe to handle?+
It contains toxic constituents. Contains silver and chlorine; avoid ingestion or inhalation of dust. Wash hands thoroughly after handling specimens. Handle with care, avoid grinding or breathing dust, and store separately.
What rocks look like cerargyrite?+
Cerargyrite is most often confused with Bromargyrite, Iodargyrite, Calcite. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with cerargyrite?+
Cerargyrite commonly co-occurs with Silver, Iodargyrite, Bromargyrite, Goethite, Galena. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does cerargyrite form in?+
Cerargyrite typically forms in oxidized zones of silver ore deposits. Working float back to the host body is the standard way to chase a fresh occurrence.
What is cerargyrite used for?+
Cerargyrite is used in collector, ore of silver.

Find cerargyrite on the map

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

Download on the App StoreGet it on Google Play