Howard City Gem Mine: Rockhounding in Kent County, Michigan

Quick details

Access

Paid / fee dig

County

Kent County

State

Michigan

Nearest road

Stacey Road

Postcode

48838

Coordinates

43.18242, -85.31951

Geology at Howard City Gem Mine

This spot sits on Saginaw Formation, mapped as sandstone and shale that formed roughly 325 to 300 million years ago. Sedimentary rock like this erodes unevenly, so the most productive collecting is typically along fresh cuts, badland slopes, and active drainages.

Mapped unit

Saginaw Formation

Age

325–300 Ma (Pennsylvanian)

Rock types

sandstone and shale

Elevation

920 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 Howard City Gem Mine

Best months: March to November. Typical highs run 84°F in midsummer and 31°F in midwinter, with winter lows near 13°F.

Climate normals: NOAA 1991-2020 monthlies, GREENVILLE 2 NNE station (4 mi away).

Land & collecting status

Pay-to-dig site

This is a fee-dig location. Hours, prices, and what you can keep vary by operator. Call ahead before driving out.

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.

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