A manatee bone fossil is usually found as a dense, heavy fragment in fluvial or marine sedimentary layers. Look for the porous structure and bone density characteristic of Sirenia, typically preserved through petrification or mineral replacement in riverbeds and coastal deposits.

Hardness

3-5

Mohs

Luster

Dull

Transparency

Opaque

fossilcommon

Manatee Bone

Also: Sirenia fossil

Hardness: 3-5
Luster: Dull
Transparency: Opaque

Is this manatee bone?

4-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 manatee bone with a known reference. Manatee Bone sits at Mohs 3-5, 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: Sirenians (manatees and dugongs). Age: Eocene (about 50 million years ago) to recent.
3
Read the luster
Hold the specimen under a strong light. Luster: dull.
4
Match the color range
Compare against the expected color range: tan, brown, gray, white, cream.

Often confused with

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

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: Petrified Wood is the harder of the two (Mohs 6.5-7 vs. 3-5); luster reads dull on Manatee Bone and vitreous to waxy on Petrified Wood.

Compare →

Often found alongside manatee bone

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

All properties

Mohs hardness: 3-5
Density: 2.0-2.5 g/cm³
Colors: Tan Brown Gray White Cream
Luster: Dull
Transparency: Opaque
Rarity: Common
Uses: Collector, Display, Educational
Host rock: sedimentary deposits
Organism: Sirenians (manatees and dugongs)
Age: Eocene (about 50 million years ago) to recent

Where rockhounds find manatee bone

3 mapped spots

Classic worldwide localities

Florida, USA
South Carolina, USA
Caribbean Islands
Brazil

Field-hunting tip

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

Browse 3 U.S. spots for manatee bone →

Common questions

How do you identify manatee bone?+

Mohs hardness is 3-5. Organism: Sirenians (manatees and dugongs). Luster: dull. Common colors include tan, brown, gray, white.

Where is manatee bone found?+

Notable localities include Florida, USA; South Carolina, USA; Caribbean Islands; Brazil.

Can I find manatee bone in the United States?+

RockHoundR maps 3 manatee bone rockhounding spots across 1 U.S. states. The top states are Florida.

What rocks look like manatee bone?+

Manatee Bone is most often confused with Petrified Wood. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with manatee bone?+

Manatee Bone commonly co-occurs with Quartz, Calcite, Phosphorite, Clay minerals. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does manatee bone form in?+

Where it forms: sedimentary deposits. Working float back to the host body is the standard way to chase a fresh occurrence.

What is manatee bone used for?+

Manatee Bone is used in collector, display, educational.

Find manatee bone on the map

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