Best spot

Knobly Mountain: Chalcedony & Calcite Rockhounding in Mineral County, West Virginia

Updated July 2026

Knobly Mountain is a classic 19th-century West Virginia mineral locality, a railroad cut on the mountain's west flank that exposed limestone yielding exceptional celestite crystals before 1890. The site is a small Mississippi Valley-type occurrence, with fluorite, sphalerite, calcite, dolomite, native sulfur, strontianite, and chalcedony filling voids in the carbonate, an unusual combination of strontium, fluorine, and zinc minerals for the state. It remains one of the best-documented ore-mineral localities in the eastern West Virginia carbonates. Reported finds include chalcedony, calcite, dolomite, fluorite, sulfur, and more. Below: coordinates, access notes, nearby spots, and trip-planning links.

Knobly Mountain photos

Public image records connected to this spot or its reported material.

1 photo

The New Creek valley below Knobly Mountain, Mineral County, West Virginia.

Quick details

Access: Public area
County: Mineral County
State: West Virginia
Postcode: 26710
Coordinates: 39.34587, -79.00290

Geology at Knobly Mountain

This spot sits on Oriskany Sandstone and Huntersville Chert, mapped as sandstone and chert that formed roughly 420 to 360 million years ago. Tough silica like agate, jasper, and chert typically weathers out of beds like these and collects as float in drainages and on deflation surfaces.

Mapped unit: Oriskany Sandstone and Huntersville Chert
Age: 420–360 Ma (Devonian)
Rock types: sandstone and chert
Elevation: 1,210 ft

Geologic mapping via Macrostrat and the underlying state geological survey maps (CC BY 4.0). Bedrock at the surface can vary within a mapped unit.

Best time to visit Knobly Mountain

Best months: March to November. Typical highs run 88°F in midsummer and 39°F in midwinter, with winter lows near 20°F.

Climate normals: NOAA 1991-2020 monthlies, KEYSER 2 SSW station (5 mi away), adjusted for elevation.

Land & collecting status

Generally open to casual rockhounding

Most public-tagged spots sit on BLM, U.S. Forest Service, or other federal land where reasonable hand collecting of common rocks and minerals is allowed. Confirm posted rules and active mining claims before you dig.

Public-land rules vary by agency, season, and field office. The RockHoundR app pulls live BLM, USFS, NPS, and tribal overlays so you can see exactly which agency manages the ground at this spot.

Sources & verification

Spot details combine the public RockHoundR location dataset, normalized mineral labels, agency land-status checks in the app, and community submissions. Coordinates are approximate until verified in the field.

Sources: RockHoundR public spot dataset, app land overlays, and local agency review before each trip.

Found at Knobly Mountain

Each chip opens all spots that produce that material; the encyclopedia link opens the full ID and field guide.

Nearby rockhounding spots

Other rockhounding spots within driving distance of Knobly Mountain.

Across the state line from Knobly Mountain

Knobly Mountain is close enough to the West Virginia border that the next-closest rockhounding spots are in a neighboring state. Worth knowing if you are already on the road.

Knobly Mountain FAQ

Where is Knobly Mountain?+

Knobly Mountain is in Mineral County, West Virginia, at 39.34587, -79.00290.

What rocks and minerals can you find at Knobly Mountain?+

Knobly Mountain is reported to produce Chalcedony, Calcite, Dolomite, Fluorite, Sulfur, Quartz, Sphalerite.

Is collecting allowed at Knobly Mountain?+

Generally open to casual rockhounding. Most public-tagged spots sit on BLM, U.S. Forest Service, or other federal land where reasonable hand collecting of common rocks and minerals is allowed. Confirm posted rules and active mining claims before you dig. Always confirm current rules with the managing agency before a trip.

What tools should I bring to Knobly Mountain?+

Most agate and jasper is surface float: bring a spray bottle, a pick or small shovel, and a sturdy bag. Wet stones show their banding and translucence.

When is the best time to visit Knobly Mountain?+

The most comfortable months at Knobly Mountain are March to November.

How do I get to Knobly Mountain?+

Open the directions link to navigate to 39.34587, -79.00290 in Google Maps. Some spots are remote, so check road conditions before driving out.

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