Elk Rapids Sandbar: Petoskey Stone & Charlevoix Stone Rockhounding in Antrim County, Michigan

Plan your visit

Confirm rules before collecting

County

Antrim County

State

Michigan

Postcode

49629

Coordinates

44.89812, -85.41853

Coordinates are approximate. Confirm the exact ground in the RockHoundR app, where land overlays show which agency manages the area.

Land & collecting status

Confirm rules before collecting

Land status here is not confirmed. Verify with the managing agency before collecting, federal, state, and tribal rules differ.

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.

Best time to visit Elk Rapids Sandbar

Comfortable months (45 to 90°F highs)

Best months: April to November. Typical highs run 80°F in midsummer and 30°F in midwinter, with winter lows near 17°F.

Climate normals: NOAA 1991-2020 monthlies, OLD MISSION 3SSW station (5 mi away).

Geology at Elk Rapids Sandbar

This spot sits on Ellsworth Shale, mapped as shale that formed roughly 385 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

Ellsworth Shale

Age

385–360 Ma (Late Devonian)

Rock types

shale

Elevation

570 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.

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.

State guidance last verified: April 1, 2026

• Michigan DNR, Rockhounding rules
• Michigan Geological Survey
• Isle Royale National Park, Rules
• Community submissions reviewed against published agency rules