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.
Is this cerargyrite?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch cerargyrite with a known reference. Cerargyrite sits at Mohs 1.5 — softer than the next harder reference, harder than the previous one.
- 2Check the streakDrag the specimen across an unglazed porcelain plate. Cerargyrite leaves a white streak.
- 3Read the lusterHold the specimen under a strong light. Cerargyrite typically shows a resinous luster.
- 4Match the color rangeCompare against the expected color range: colorless, white, gray, yellowish, brownish, violet.
- 5Look at form & habitCrystal 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.

How to tell apart: Streak differs — Cerargyrite leaves white, Bromargyrite leaves yellowish-white.

How to tell apart: Streak differs — Cerargyrite leaves white, Iodargyrite leaves yellow.

How to tell apart: Calcite is the harder of the two (Mohs 3 vs. 1.5); luster reads resinous on Cerargyrite and vitreous on Calcite.
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 spotsClassic 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.



