Itacolumite is a porous, flexible variety of sandstone that contains grains of mica, which provide the internal slippage necessary for its characteristic flexibility. When thin slabs are supported at the ends, they can be noticeably bent by hand. It is primarily found in metamorphic regions and is famous for its rarity as a naturally flexible rock.
Is this itacolumite?
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 itacolumite with a known reference. Itacolumite sits at Mohs 6-7, softer than the next harder reference, harder than the previous one.
- 2Read the textureLook at a fresh break with a hand lens. Texture: Porous, with interlocking quartz sand grains.
- 3Pick out the mineralsComposition: Almost pure quartz with scales of greenish mica. 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: yellow, brown, tan, gray.
Often confused with
Itacolumite vs. its common look-alikes, and how to tell them apart in the field.
Often found alongside itacolumite
Minerals reported to co-occur with itacolumite. Spotting these in float or country rock is a strong cue you are in the right ground.
All properties
- Mohs hardness
- 6-7
- Density
- 2.6-2.7 g/cm³
- Luster
- Dull
- Transparency
- Opaque
- Rarity
- Uncommon
- Uses
- Collector, Decorative, Scientific
- Host rock
- metamorphic sedimentary
- Texture
- Porous, with interlocking quartz sand grains
- Composition
- Almost pure quartz with scales of greenish mica
Where rockhounds find itacolumite
2 mapped spotsClassic worldwide localities
- Minas Gerais, Brazil
- Delhi, India
- North Carolina, USA
- Georgia, USA
Field-hunting tip
Where it forms: metamorphic sedimentary. If you start seeing quartz, mica, hematite in float, you are in the right ground. In the U.S., the densest reported localities are in Georgia, North Carolina. Start trip planning there.
Common questions
How do you identify itacolumite?+
Where is itacolumite found?+
Can I find itacolumite in the United States?+
What rocks look like itacolumite?+
What minerals are found with itacolumite?+
What kind of rock does itacolumite form in?+
What is itacolumite used for?+
Find itacolumite on the map
RockHoundR shows mapped rockhounding spots, access rules, and lets you log every find.
