What Are Honeycomb Rocks?
Honeycomb rocks are known by many names. Some of the alternative names for them include:
- Honeycomb rocks
- Honeycomb weathering
- Cavernous weathering
- Stone lace
- Lattice stone or stone lattice
- Alveolar weathering
- Miniature tafoni weathering
What Are Honeycomb Rocks?
Honeycomb rocks are rocks formed by an intricate dance of weathering, chemistry, and mountain building. But it's a long, slow dance; honeycomb rocks take millions of years to form.
Honeycomb rocks are stones that have a pattern of lattice-works or cells in the surface. This pattern resembles a honeycomb, from which the pattern takes its name.
Some honeycomb weathering occurs on man-made objects, such as buildings and walls made of stone. Softer rocks can form a honeycomb pattern. But true honeycomb rocks, such as the ones I photographed in West Virginia as part of this story, are caused by the confluence of several natural geological processes. The confluence of these processes forms the patterns on the rocks.
If the rocks could talk, the Honeycomb Rocks I photographed in West Virginia would share a story of centuries of water, wind, temperature and creeping movement.
West Virginia's Honeycomb Rocks
The honeycomb rocks shown here were formed during the mountain-building process which created the Appalachian Mountains in the United States. Rock bending, a process in which pressure actually bends or folds rock faces, occurred throughout the Appalachians and created fractures. These fractures in the rocks allowed water to flow over the surface. Iron-rich waters found in the area created a chemical interaction with the Sharon Sandstone and Kaolinite deposits in the rocks. The iron-rich water dissolved the sandstone and kaolinite. In its place, Hematite (Fe2 O3), a common iron oxide, was left behind.
When water is hot and acidic enough as it was in ancient times in this area, it can actually dissolve iron and other hard minerals. In the case of the Honeycomb Rocks of West Virginia, the iron-rich water solution washed over the fractures in the sandstone and kaolinite in the rocks. Hematite replaces kaolinite. The boxwork lattice found inside the honeycomb rocks looks red and rusty because this iron-rich Hematite replaced kaolinite.
Timeline of Honeycomb Rocks Formation
400 Million Years Before the Cell Phone Came Coalstone
If you had a time machine, you could set it to around 360 - 400 million years ago and see the start of the Honeycomb Rocks formation. Around 320 to 360 million years ago, sediment was deposited in layers in the area we now know as the Appalachians. This sediment consisted of shale, followed by Shale conglomerate, and shale and coal sandstone.
Geologists refer to this time period as the late Mississippian Period and the Early Pennsylvanian Period.
200 Million Years Ago, Fracture Patterns Made It Pretty
200 million years ago, the process of fracturing began. Fractures and cracks created by the tremendous forces of mountain movements made the patterns you see today in the Honeycomb Rocks.
Over the next hundred million years or so, water flowed through the fractures. This water was hot, and the heat and acidic nature of the water dissolved various minerals in the water, creating the perfect blend to start transforming the substance of the rocks. (Who said alchelmy is a myth never saw Honeycomb Rocks!
As the hot, mineral-rich water flowed over the kaolinite lattice work in the sandstone, kaolinite dissolved. Hematite replaced kaolinite, forming hard, rigid cells in the rock.
Erosion, or the force of wind, temperature and rain, further dissolved the sandstone, revealing the mysterious and intricate patterns of the Honeycomb Rocks.
Where to See Honeycomb Rocks
See these rocks on the Honeycomb Rock Trail, Highland Scenic Highway (State Route 150) in Pocahontas County, West Virginia.
See Them in Person
There are many examples of honeycomb rocks and honeycomb weathering, but the photos accompanying this article were taken along the Honeycomb Rocks Trail, Highland Scenic Highway (State Highway 150) in Pocahontas County, West Virginia. Other places to see in the area include the Cranberry Glade Bog Trail and the Greenbriar River Trail.
The trail is an easy walking trail with ample parking. The trail is paved, and although it does climb up and down a bit, you could traverse it with a stroller or wheelchair. Follow the signage on the trail to see the rocks in order, from 1 to 10. Each marker explains a segment of the geological processes that formed these intriguing rocks.
For More Information
- TLC "West Virginia Scenic Drives: Highland Scenic Highway"
West Virginia's Highland Scenic Highway offers miles of unspoiled views. Check out details, maps, and photos for this stunning scenic drive.
- Honeycomb weathering - Wikipedia, the free encyclopedia
© 2013 Jeanne Grunert