Best spot

Spearfish Canyon: Geode Digging in Lawrence County, South Dakota

Updated June 2026

Lawrence County in the northern Black Hills is the best part of South Dakota for geodes, and the gravels in and around Spearfish Canyon yield baseball-sized geodes lined with amethyst, quartz, and chalcedony, plus silicified wood. The canyon is also one of the most scenic settings for rockhounding in the state. Reported finds include amethyst, geode, chalcedony, silicified wood. Below: coordinates, access notes, nearby spots, and trip-planning links.

Spearfish Canyon photos

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

1 photo

An amethyst geode lined with purple quartz crystals and a white chalcedony rim, the kind of crystal-lined geode found in the northern Black Hills gravels

Quick details

Access: Public area
County: Lawrence County
State: South Dakota
Nearest road: US Highway 14A
Coordinates: 44.34701, -103.92440

Geology at Spearfish Canyon

This spot sits on ground mapped as Deadwood Formation that formed roughly 495 to 470 million years ago. Geodes typically weather free of their host rock and collect as rounded float in soils and drainages.

Mapped unit: Deadwood Formation
Age: 495–470 Ma (Late Cambrian to Early Ordovician)
Elevation: 5,060 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 Spearfish Canyon

Best months: March to November. Typical highs run 82°F in midsummer and 38°F in midwinter, with winter lows near 18°F.

Climate normals: NOAA 1991-2020 monthlies, LEAD station (9 mi away).

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 Spearfish Canyon

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 Spearfish Canyon.

Across the state line from Spearfish Canyon

Spearfish Canyon is close enough to the South Dakota border that the next-closest rockhounding spots are in a neighboring state. Worth knowing if you are already on the road.

Spearfish Canyon FAQ

Where is Spearfish Canyon?+

Spearfish Canyon is in Lawrence County, South Dakota, at 44.34701, -103.92440. Nearest road: US Highway 14A.

What rocks and minerals can you find at Spearfish Canyon?+

Spearfish Canyon is reported to produce Amethyst, Geode, Chalcedony, Silicified Wood.

Is collecting allowed at Spearfish Canyon?+

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 Spearfish Canyon?+

Bring a crack hammer, a chisel, safety glasses, and a bucket. Candidates are rounder and lighter than solid rock; a soil pipe cutter opens them cleaner than a flat smash.

When is the best time to visit Spearfish Canyon?+

The most comfortable months at Spearfish Canyon are March to November.

How do I get to Spearfish Canyon?+

Open the directions link to navigate to 44.34701, -103.92440 in Google Maps. The nearest road is US Highway 14A.

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