Protozoa agate is a form of chalcedony that has replaced biological remains, often displaying microscopic, intricate patterns characteristic of fossilized microorganisms. Collectors look for unique banding and internal structures that indicate its ancient biological origin, typically found in sedimentary formations. It is highly sought after by lapidary enthusiasts for its aesthetic, pattern-rich cabochons.

Hardness
6.5-7
Mohs
Luster
Vitreous
Transparency
Translucent

Is this protozoa agate?

3-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 protozoa agate with a known reference. Protozoa Agate sits at Mohs 6.5-7, softer than the next harder reference, harder than the previous one.
  • 2
    Read the luster
    Hold the specimen under a strong light. Luster: vitreous.
  • 3
    Match the color range
    Compare against the expected color range: brown, red, yellow, white, gray.

Often confused with

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

Often found alongside protozoa agate

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

All properties

Mohs hardness
6.5-7
Density
2.6-2.7 g/cm³
Luster
Vitreous
Transparency
Translucent
Rarity
Uncommon
Uses
Lapidary, Collector, Decorative
Host rock
sedimentary

Where rockhounds find protozoa agate

1 mapped spots

Classic worldwide localities

  • Wyoming, USA
  • Montana, USA

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 Iowa. Start trip planning there.

More protozoa agate photos

  • Turritella agate showing densely packed fossil gastropod shells
  • Cut Turritella agate: Elimia tenera gastropods in fossiliferous chert, Wyoming

Common questions

How do you identify protozoa agate?+
Mohs hardness is 6.5-7. Luster: vitreous. Common colors include brown, red, yellow, white.
Where is protozoa agate found?+
Notable localities include Wyoming, USA; Montana, USA.
Can I find protozoa agate in the United States?+
RockHoundR maps 1 protozoa agate rockhounding spots across 1 U.S. states. The top states are Iowa.
What rocks look like protozoa agate?+
Protozoa Agate is most often confused with Chert, Jasper. A quick hardness test and a streak check separate the look-alikes faster than color alone.
What minerals are found with protozoa agate?+
Protozoa Agate commonly co-occurs with Quartz, Chalcedony, Calcite. Spotting any of these in float or country rock is a useful trip signal.
What kind of rock does protozoa agate form in?+
Where it forms: sedimentary. Working float back to the host body is the standard way to chase a fresh occurrence.
What is protozoa agate used for?+
Protozoa Agate is used in lapidary, collector, decorative.

Find protozoa agate on the map

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

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