Mill Creek: Manganese Rockhounding in Johnston County, Oklahoma

Updated June 2026

Mill Creek is a mapped rockhounding spot in Johnston County, Oklahoma. Reported finds include manganese. Below: coordinates, access notes, nearby spots, and trip-planning links.

Quick details

Access: Check locally
County: Johnston County
State: Oklahoma
Nearest road: Center Road
Postcode: 74856
Coordinates: 34.40994, -96.80749

Geology at Mill Creek

This spot sits on Oil Creek and Joins Formation, mapped as limestone, shale, and sandstone that formed roughly 470 to 460 million years ago. Carbonate rock like this dissolves and weathers readily, so fresh road cuts, quarries, and creek exposures are typically the most productive ground.

Mapped unit: Oil Creek and Joins Formation
Age: 470–460 Ma (Middle Ordovician)
Rock types: limestone, shale, and sandstone
Elevation: 1,040 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 Mill Creek

Best months: September to June. Typical highs run 92°F in midsummer and 52°F in midwinter, with winter lows near 29°F.

Climate normals: NOAA 1991-2020 monthlies, TISHOMINGO 6N MESONET station (9 mi away), adjusted for elevation.

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.

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 Mill Creek

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

Manganese Encyclopedia →

Nearby rockhounding spots

Other rockhounding spots within driving distance of Mill Creek.

Mill Creek FAQ

Where is Mill Creek?+

Mill Creek is in Johnston County, Oklahoma, at 34.40994, -96.80749. Nearest road: Center Road.

What rocks and minerals can you find at Mill Creek?+

Mill Creek is reported to produce Manganese.

Is collecting allowed at Mill Creek?+

Confirm rules before collecting. Land status here is not confirmed. Verify with the managing agency before collecting — federal, state, and tribal rules differ. Always confirm current rules with the managing agency before a trip.

What tools should I bring to Mill Creek?+

A rock hammer, sturdy gloves, safety glasses, and a collecting bag cover the basics here. Add a spray bottle: wet rock shows color and pattern that dry rock hides.

When is the best time to visit Mill Creek?+

The most comfortable months at Mill Creek are September to June.

How do I get to Mill Creek?+

Open the directions link to navigate to 34.40994, -96.80749 in Google Maps. The nearest road is Center Road.

More rockhounding in Oklahoma

See all 36 Oklahoma spots →

Open Mill Creek on the map

Use the RockHoundR app for live land overlays, weather, geology, directions, and saved finds.