Coquina is a sedimentary rock composed almost entirely of poorly cemented shell fragments and mollusk debris. It is easily identified by its highly porous, conglomerate-like appearance and its distinct lack of a fine-grained matrix. It is commonly found in beach and shallow marine environments where high wave energy prevents the accumulation of silt.

Hardness

Mohs

Luster

Dull

Streak

White

Transparency

Opaque

sedimentarycommon

Coquina

Hardness: 3
Luster: Dull
Streak: White
Transparency: Opaque

Is this coquina?

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 coquina with a known reference. Coquina sits at Mohs 3, softer than the next harder reference, harder than the previous one.
2
Check the streak
Drag the specimen across an unglazed porcelain plate. Coquina leaves a white streak.
3
Read the luster
Hold the specimen under a strong light. Coquina typically shows a dull luster.
4
Match the color range
Compare against the expected color range: tan, white, light gray.
5
Look at form & habit
Typical habit: massive.

Often confused with

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

sedimentary

Limestone

Mohs 3

How to tell apart: Luster reads dull on Coquina and dull to earthy on Limestone.

Compare →

Often found alongside coquina

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

All properties

Mohs hardness: 3
Density: 2.0-2.5 g/cm³
Colors: Tan White Light Gray
Streak: White
Luster: Dull
Transparency: Opaque
Crystal habit: Massive
Cleavage: None
Rarity: Common
Uses: Construction, Decorative, Ornamental
Host rock: Marine Environments
Typical price: $5-30 per specimen

Where rockhounds find coquina

2 mapped spots

Classic worldwide localities

Florida, USA
Saint Augustine, USA
Western Australia
Brazil
Spain

Field-hunting tip

Look in marine environments country, the host setting where coquina typically forms. If you start seeing calcite, quartz, aragonite in float, you are in the right ground. Field specimens usually show a massive habit, so train your eye for that shape before scanning the outcrop. In the U.S., the densest reported localities are in Florida. Start trip planning there.

Browse 2 U.S. spots for coquina →

Common questions

How do you identify coquina?+

Mohs hardness is 3. It typically shows a dull luster. The streak is white. Common colors include tan, white, light gray.

Where is coquina found?+

Notable localities include Florida, USA; Saint Augustine, USA; Western Australia; Brazil; Spain.

Can I find coquina in the United States?+

RockHoundR maps 2 coquina rockhounding spots across 1 U.S. states. The top states are Florida.

How much is coquina worth?+

Typical asking prices fall in the range of $5-30 per specimen. Quality, size, and provenance can move individual specimens well outside that range.

What rocks look like coquina?+

Coquina is most often confused with Limestone. A quick hardness test and a streak check separate the look-alikes faster than color alone.

What minerals are found with coquina?+

Coquina commonly co-occurs with Calcite, Quartz, Aragonite. Spotting any of these in float or country rock is a useful trip signal.

What kind of rock does coquina form in?+

Coquina typically forms in marine environments. Working float back to the host body is the standard way to chase a fresh occurrence.

What is coquina used for?+

Coquina is used in construction, decorative, ornamental.

Find coquina on the map

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