Fossils are the preserved remains, impressions, or traces of ancient life found in sedimentary rocks. They often undergo mineralization where original material is replaced by silica, calcite, or pyrite, resulting in detailed replicas of ancient biological structures.

Hardness

3-7

Mohs

Luster

Dull to Vitreous

Streak

White

Transparency

Opaque

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Fossils

Hardness: 3-7
Luster: Dull to Vitreous
Streak: White
Transparency: Opaque

Is this fossils?

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 fossils with a known reference. Fossils sits at Mohs 3-7 — softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Fossils leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Fossils typically shows a dull to vitreous luster.
4
Match the color range
Compare against the expected color range: brown, gray, white, tan, black.
5
Look at form & habit
Typical habit: pseudomorphs after organic structures.

Often found alongside fossils

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

All properties

Mohs hardness: 3-7
Density: 2.0-3.0 g/cm³
Colors: Brown Gray White Tan Black
Streak: White
Luster: Dull to Vitreous
Transparency: Opaque
Crystal habit: Pseudomorphs After Organic Structures
Cleavage: None
Fluorescence: Variable
Rarity: Common
Uses: Collector, Educational, Decorative, Lapidary
Host rock: Sedimentary Strata
Typical price: $5-500 depending on preservation and rarity

Where rockhounds find fossils

90 mapped spots

Classic worldwide localities

Morocco
USA (Wyoming)
Germany
China
Madagascar

U.S. states with fossils

Each link opens a state-specific list of mapped rockhounding spots that produce fossils.

Field-hunting tip

Look in sedimentary strata country — that is the host setting where fossils typically forms. If you start seeing calcite, quartz, pyrite in float, you are in the right ground. Field specimens usually show a pseudomorphs after organic structures habit, so train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in Nebraska, Missouri, Florida — start trip planning there.

Browse 90 U.S. spots for fossils →

Common questions

How do you identify fossils?+

Mohs hardness is 3-7. It typically shows a dull to vitreous luster. The streak is white. Common colors include brown, gray, white, tan.

Where is fossils found?+

Notable localities include Morocco; USA (Wyoming); Germany; China; Madagascar.

Can I find fossils in the United States?+

RockHoundR maps 90 fossils rockhounding spots across 12 U.S. states — the top states are Nebraska, Missouri, Florida.

How much is fossils worth?+

Typical asking prices fall in the range of $5-500 depending on preservation and rarity. Quality, size, and provenance can move individual specimens well outside that range.

What minerals are found with fossils?+

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

What kind of rock does fossils form in?+

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

What is fossils used for?+

Fossils is used in collector, educational, decorative, lapidary.

Find fossils on the map

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