Cervantite is a secondary antimony oxide mineral that typically forms as an alteration product of stibnite. It is most commonly found as earthy or crust-like coatings in oxidized ore zones, rarely as distinct acicular crystals.

Hardness
4-5
Mohs
Luster
Greasy
Streak
White
Transparency
Translucent

Is this cervantite?

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 cervantite with a known reference. Cervantite sits at Mohs 4-5 — softer than the next harder reference, harder than the previous one.
  • 2
    Check the streak
    Drag the specimen across an unglazed porcelain plate. Cervantite leaves a white streak.
  • 3
    Read the luster
    Hold the specimen under a strong light. Cervantite typically shows a greasy luster.
  • 4
    Match the color range
    Compare against the expected color range: yellow, white, gray.
  • 5
    Look at form & habit
    Crystal system: orthorhombic. Typical habit: acicular crystals, earthy or massive crusts, pseudomorphs after stibnite.

Often confused with

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

Often found alongside cervantite

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

All properties

Chemical formula
Sb₂O₄
Mohs hardness
4-5
Density
6.64 g/cm³
Streak
White
Luster
Greasy
Transparency
Translucent
Crystal system
Orthorhombic
Crystal habit
Acicular Crystals, Earthy or Massive Crusts, Pseudomorphs After Stibnite
Cleavage
None
Rarity
Uncommon
Uses
Collector
Host rock
Oxidized Zones of Antimony Deposits
Typical price
$10-50 per specimen

Where rockhounds find cervantite

1 mapped spots

Classic worldwide localities

  • Cervantes, Spain
  • Kern County, California, USA
  • Hunan, China
  • Broken Hill, Australia

Field-hunting tip

Look in oxidized zones of antimony deposits country — that is the host setting where cervantite typically forms. If you start seeing stibnite, valentinite, kermesite in float, you are in the right ground. Field specimens usually show a acicular crystals, earthy or massive crusts, pseudomorphs after stibnite habit, so train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in South Dakota — start trip planning there.

Common questions

How do you identify cervantite?+
Mohs hardness is 4-5. It typically shows a greasy luster. The streak is white. Common colors include yellow, white, gray.
Where is cervantite found?+
Notable localities include Cervantes, Spain; Kern County, California, USA; Hunan, China; Broken Hill, Australia.
Can I find cervantite in the United States?+
RockHoundR maps 1 cervantite rockhounding spots across 1 U.S. states — the top states are South Dakota.
How much is cervantite worth?+
Typical asking prices fall in the range of $10-50 per specimen. Quality, size, and provenance can move individual specimens well outside that range.
Is cervantite safe to handle?+
It contains toxic constituents. Contains antimony, which is toxic if ingested or inhaled as dust. Wash hands thoroughly after handling specimens. Handle with care, avoid grinding or breathing dust, and store separately.
What rocks look like cervantite?+
Cervantite is most often confused with Stibiconite, Senarmontite, Valentinite. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with cervantite?+
Cervantite commonly co-occurs with stibnite, valentinite, kermesite, stibiconite. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does cervantite form in?+
Cervantite typically forms in oxidized zones of antimony deposits. Working float back to the host body is the standard way to chase a fresh occurrence.
What is cervantite used for?+
Cervantite is used in collector.

Find cervantite on the map

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

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