Novaculite is a dense, hard, cryptocrystalline sedimentary rock composed primarily of microcrystalline quartz. It is famous for its use as a high-quality sharpening stone due to its uniform texture and abrasive nature, often found in the Ouachita Mountains of North America.
Is this novaculite?
5-step field checkRun through these checks against the specimen in your hand. The more boxes tick, the more confident the ID.
- 1Test the hardnessTry to scratch novaculite with a known reference. Novaculite sits at Mohs 7, softer than the next harder reference, harder than the previous one.
- 2Read the textureLook at a fresh break with a hand lens. Texture: Microcrystalline to cryptocrystalline. Grain size: Crystals 3 to 5 microns.
- 3Pick out the mineralsComposition: Silica in the form of chert or flint. Identify the two or three most abundant grains.
- 4Read the lusterHold the specimen under a strong light. Luster: dull.
- 5Match the color rangeCompare against the expected color range: white, gray, black, yellow.
Often confused with
Novaculite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside novaculite
Minerals reported to co-occur with novaculite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Mohs hardness
- 7
- Density
- 2.65 g/cm³
- Luster
- Dull
- Transparency
- Opaque
- Rarity
- Common
- Uses
- Lapidary, Industrial
- Host rock
- sedimentary novaculite beds
- Texture
- Microcrystalline to cryptocrystalline
- Grain size
- Crystals 3 to 5 microns
- Composition
- Silica in the form of chert or flint
Where rockhounds find novaculite
3 mapped spotsClassic worldwide localities
- Arkansas, USA
- Oklahoma, USA
Field-hunting tip
Where it forms: sedimentary novaculite beds. If you start seeing quartz in float, you are in the right ground. In the U.S., the densest reported localities are in Oklahoma, Massachusetts. Start trip planning there.
More novaculite photos
Common questions
How do you identify novaculite?+
Where is novaculite found?+
Can I find novaculite in the United States?+
What rocks look like novaculite?+
What minerals are found with novaculite?+
What kind of rock does novaculite form in?+
What is novaculite used for?+
Find novaculite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
