RockHoundR

Dinosaur bone is fossilized biological material in which the original bone structure has been replaced by silica, typically chalcedony or quartz. Collectors look for the distinct honeycomb or cell structure of the cancellous bone preserved in a polished cross-section. It occurs in Mesozoic sedimentary deposits where mineral-rich groundwater permeated the skeletal remains.

Hardness
5.5-7
Mohs
Luster
Waxy
Transparency
Opaque

Is this dinosaur bone?

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 dinosaur bone with a known reference. Dinosaur Bone sits at Mohs 5.5-7, softer than the next harder reference, harder than the previous one.
  • 2
    Name the organism
    Decide what left the fossil before worrying about the rock. Organism: Dinosaurs. Age: Triassic to the end of the Cretaceous (66 million years ago) for non-avian dinosaurs.
  • 3
    Check the preservation
    Preservation: Permineralization: minerals fill the pores of bone. That controls the weight, the hardness and how the piece takes a polish.
  • 4
    Read the luster
    Hold the specimen under a strong light. Luster: waxy.
  • 5
    Match the color range
    Compare against the expected color range: brown, red, black, tan, gray, white.

Often confused with

Dinosaur Bone vs. its common look-alikes, and how to tell them apart in the field.

Agate mineral
mineral
Agate
Mohs 6.5-7
Compare →
Polished deep-red opaque jasper
mineral
Jasper
Mohs 6.5-7
Compare →
A petrified log section lying on desert ground, red and orange against bare dirt
fossil
Petrified Wood
Mohs 6.5-7

How to tell apart: Luster reads waxy on Dinosaur Bone and vitreous to waxy on Petrified Wood.

Compare →

Often found alongside dinosaur bone

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

All properties

Mohs hardness
5.5-7
Density
2.5-2.8 g/cm³
Colors
BrownRedBlackTanGrayWhite
Luster
Waxy
Transparency
Opaque
Rarity
Common
Uses
Lapidary, Collector, Ornamental, Display
Host rock
sedimentary
Organism
Dinosaurs
Age
Triassic to the end of the Cretaceous (66 million years ago) for non-avian dinosaurs
Preservation
Permineralization: minerals fill the pores of bone

Where rockhounds find dinosaur bone

2 mapped spots

Classic worldwide localities

  • Utah
  • Colorado
  • Wyoming
  • Madagascar
  • Morocco

Field-hunting tip

Where it forms: sedimentary. If you start seeing quartz, chalcedony, calcite in float, you are in the right ground. In the U.S., the densest reported localities are in Wyoming. Start trip planning there.

Browse 2 U.S. spots for dinosaur bone →

Common questions

How do you identify dinosaur bone?+
Mohs hardness is 5.5-7. Organism: Dinosaurs. Preservation: Permineralization: minerals fill the pores of bone. Luster: waxy. Common colors include brown, red, black, tan.
Where is dinosaur bone found?+
Notable localities include Utah; Colorado; Wyoming; Madagascar; Morocco.
Can I find dinosaur bone in the United States?+
RockHoundR maps 2 dinosaur bone rockhounding spots across 1 U.S. states. The top states are Wyoming.
What rocks look like dinosaur bone?+
Dinosaur Bone is most often confused with Agate, Jasper, Petrified Wood. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with dinosaur bone?+
Dinosaur Bone commonly co-occurs with Quartz, Chalcedony, Calcite, Pyrite. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does dinosaur bone form in?+
Where it forms: sedimentary. Working float back to the host body is the standard way to chase a fresh occurrence.
What is dinosaur bone used for?+
Dinosaur Bone is used in lapidary, collector, ornamental, display.

Find dinosaur bone on the map

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

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