Marble is a metamorphic rock formed by the recrystallization of limestone or dolostone under heat and pressure. It is prized by sculptors and architects for its uniform grain and ability to take a high polish. Collectors typically look for pieces with interesting veining caused by impurities like clay, silt, or iron oxides during the metamorphic process.
Is this marble?
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 marble with a known reference. Marble sits at Mohs 3-4, softer than the next harder reference, harder than the previous one.
- 2Read the textureLook at a fresh break with a hand lens. Texture: Crystalline; typically not foliated.
- 3Pick out the mineralsComposition: Recrystallized carbonate minerals, most commonly calcite or dolomite; veins and swirls from impurities such as clay, sand, iron oxides or chert. Identify the two or three most abundant grains.
- 4Read the lusterHold the specimen under a strong light. Luster: subvitreous.
- 5Match the color rangeCompare against the expected color range: white, gray, black, yellow, green, pink, red.
Often confused with
Marble vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside marble
Minerals reported to co-occur with marble. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Mohs hardness
- 3-4
- Density
- 2.5-2.7 g/cm³
- Luster
- Subvitreous
- Transparency
- Opaque
- Rarity
- Common
- Uses
- Decorative, Construction, Sculpture, Lapidary
- Host rock
- metamorphic terrain
- Texture
- Crystalline; typically not foliated
- Composition
- Recrystallized carbonate minerals, most commonly calcite or dolomite; veins and swirls from impurities such as clay, sand, iron oxides or chert
Where rockhounds find marble
7 mapped spotsClassic worldwide localities
- Carrara, Italy
- Pentelicus, Greece
- Vermont, USA
- Makrana, India
- Danby, Vermont
Field-hunting tip
Where it forms: metamorphic terrain. If you start seeing calcite, dolomite, graphite in float, you are in the right ground. In the U.S., the densest reported localities are in Maryland, Alabama, Nevada. Start trip planning there.
More marble photos
Common questions
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Find marble on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
