Ammonites are extinct marine mollusks known for their iconic coiled, spiral shells. Collectors look for intricate suture patterns on the shell surface or high-quality iridescence known as ammolite in specific fossilized specimens found primarily in Alberta, Canada.

Hardness

3-4

Mohs

Luster

Dull to Pearly

Streak

White

Transparency

Opaque

fossilcommon

Ammonites

Also: Ammonoidea

Hardness: 3-4
Luster: Dull to Pearly
Streak: White
Transparency: Opaque

Is this ammonites?

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 ammonites with a known reference. Ammonites sits at Mohs 3-4 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Ammonites leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Ammonites typically shows a dull to pearly luster.
4
Match the color range
Compare against the expected color range: brown, gray, black, white, iridescent.
5
Look at form & habit
Typical habit: coiled shell.

Often found alongside ammonites

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

All properties

Mohs hardness: 3-4
Density: 2.5-2.9 g/cm³
Colors: Brown Gray Black White Iridescent
Streak: White
Luster: Dull to Pearly
Transparency: Opaque
Crystal habit: Coiled Shell
Cleavage: None
Rarity: Common
Uses: Collector, Decorative, Educational
Host rock: Sedimentary Rocks
Typical price: $5-50 for small specimens, $200-2000+ for large polished pairs or iridescent specimens

Where rockhounds find ammonites

1 mapped spots

Classic worldwide localities

Madagascar
Morocco
United Kingdom
Germany
Canada

Field-hunting tip

Look in sedimentary rocks country — that is the host setting where ammonites typically forms. If you start seeing pyrite, calcite, quartz in float, you are in the right ground. Field specimens usually show a coiled shell habit, so train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in Wyoming — start trip planning there.

Browse 1 U.S. spots for ammonites →

Common questions

How do you identify ammonites?+

Mohs hardness is 3-4. It typically shows a dull to pearly luster. The streak is white. Common colors include brown, gray, black, white.

Where is ammonites found?+

Notable localities include Madagascar; Morocco; United Kingdom; Germany; Canada.

Can I find ammonites in the United States?+

RockHoundR maps 1 ammonites rockhounding spots across 1 U.S. states — the top states are Wyoming.

How much is ammonites worth?+

Typical asking prices fall in the range of $5-50 for small specimens, $200-2000+ for large polished pairs or iridescent specimens. Quality, size, and provenance can move individual specimens well outside that range.

What minerals are found with ammonites?+

Ammonites commonly co-occurs with pyrite, calcite, quartz. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does ammonites form in?+

Ammonites typically forms in sedimentary rocks. Working float back to the host body is the standard way to chase a fresh occurrence.

What is ammonites used for?+

Ammonites is used in collector, decorative, educational.

Find ammonites on the map

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