Where to Find Marcasite in Missouri

Missouri marcasite is the orthorhombic cousin of pyrite, found in the same Mississippi Valley dolomite host rocks. The Tri-State chat piles around Joplin in Jasper and Newton counties yield bladed marcasite rosettes and cockscomb aggregates, often pseudomorphing after pyrite. The Viburnum Trend mines (Buick, Brushy Creek, Sweetwater) produce blocky marcasite on dolomite with galena and sphalerite associations. The Old Lead Belt around Bonne Terre adds tabular and stalactitic marcasite. Surface marcasite oxidizes quickly to a sulfuric film and crumbles within months, so specimens should be coated with a thin lacquer if displayed in humid environments.

Best counties for marcasite in Missouri

Ranked by the number of mapped marcasite spots. County links open the full rockhounding page for that county.

Crawford County4 spots
Boone County2 spots
Franklin County1 spot
Greene County1 spot
Iron County1 spot
Jackson County1 spot
Jefferson County1 spot
Laclede County1 spot
Lincoln County1 spot
Madison County1 spot
Moniteau County1 spot
Phelps County1 spot
Ralls County1 spot
Saint Charles County1 spot
Washington County1 spot

Every marcasite spot we track in Missouri

Sorted by county. Coordinates open in Google Maps.

Spot	County	Minerals	Coordinates	Access
Adrian’s QuarryUS 63	Boone County	Calcite Chalcopyrite Marcasite Millerite Pyrite	38.6723, -92.2290	Public
Finger Lakes State ParkEast Peabody Haul Road	Boone County	Aragonite Copiapite Gypsum Halotrichite Marcasite Melanterite Pyrite	39.0803, -92.3031	Public
Copper Hill MineWatson Road	Crawford County	Azurite Barite Chalcopyrite Gypsum Hematite Malachite Marcasite Pyrite +1 more	38.1872, -91.1082	Public
Crooked Creek CraterCedar Drive	Crawford County	Barite Galena Marcasite Pyrite Sphalerite	37.8330, -91.4113	Public
Hinch Copper MineChristy Mine Road	Crawford County	Copper Cuprite Limonite Hematite Malachite Marcasite	38.0351, -91.1448	Public
SteelvilleStoney Ridge Lane	Crawford County	Allophane Amethyst Azurite Dolomite Galena Goethite Hematite Malachite +4 more	38.0247, -91.2273	Public
Ruepple Iron MineSpring Oak Lane	Franklin County	Amethyst Goethite Hematite Marcasite Melanterite Pyrite Quartz Siderite +4 more	38.2708, -91.1408	Public
SpringfieldEast Chestnut Expressway	Greene County	Barite Calcite Cerussite Dickite Dolomite Galena Limonite Marcasite +2 more	37.2098, -93.2264	Public
Bixby	Iron County	Bornite Chalcocite Chalcopyrite Galena Malachite Marcasite Millerite Pyrite +1 more	37.6029, -91.1169	Public
Kansas CityEast 63rd Street	Jackson County	Aragonite Barite Calcite Dolomite Marcasite Common Opal	39.0146, -94.5000	Public
ArnoldRichardson Road	Jefferson County	Geode Dolomite Marcasite Pyrite Sphalerite Calcite	38.4192, -90.3896	Public
Decaturville CraterLilac Rd	Laclede County	Albite Galena Glauconite Limonite Marcasite Microcline Muscovite Opal +4 more	37.8930, -92.7085	Public
TroyHampel Road	Lincoln County	Calcite Marcasite Pyrite Chalcopyrite Malachite Millerite Quartz Sphalerite	38.9185, -90.9386	Public
FredericktownCounty Road 274	Madison County	Aragonite Azurite Calcite Cerussite Chalcocite Chalcopyrite Dolomite Galena +5 more	37.6154, -90.2847	Public
Eldon & EttervilleHobby Horse Road	Moniteau County	Barite Calcite Cerussite Dolomite Galena Malachite Marcasite Pyrite +3 more	38.4400, -92.5802	Public
Moselle Iron MinesCounty Road 7240	Phelps County	Amethyst Arsenopyrite Azurite Chalcopyrite Hematite Malachite Marcasite Pyrite +1 more	37.8346, -91.8288	Public
HannibalRevere Trail	Ralls County	Marcasite Pyrite	39.6683, -91.3353	Public
Defiance QuarryMO DD	Saint Charles County	Yellow Calcite White Calcite Goethite Marcasite Pyrite Sphalerite Fossils	38.6608, -90.7760	Public
Old MinesMO 21;MO 47	Washington County	Barite Calcite Galena Goethite Malachite Marcasite Pyrite Chert +1 more	38.0152, -90.7561	Public

Before you go

Read the marcasite identification guide so you know what a keeper looks like in the field: Marcasite in the encyclopedia.

Marcasite in Missouri FAQ

Where can you find marcasite in Missouri?+

The mapped spots concentrate in Crawford County County, Boone County County, and Franklin County County. Known collecting areas include Joplin chat field (Jasper County), Buick mine (Iron County), and Old Lead Belt dumps (St. Francois County). Every spot on this page appears on the map above with coordinates and access notes.

How many marcasite spots are mapped in Missouri?+

19 spots across 15 counties. The RockHoundR app keeps the same spots on an offline map with public land overlays, geology layers, and your saved finds.

Is it legal to collect marcasite in Missouri?+

Hand collecting of common rocks and minerals in small amounts for personal use is generally allowed on BLM and U.S. Forest Service land, with limits set by the local field office. National parks, most state parks, and tribal land are closed to collecting. 19 of the 19 mapped spots here sit on land marked public. Always confirm current rules with the managing agency before you dig.

How do you identify marcasite found in Missouri?+

Marcasite has the same brassy color as pyrite but is paler and cleaves into bladed plates. A fresh fracture shows tabular outline; pyrite breaks conchoidal.

Where else to find marcasite

More minerals to hunt in Missouri

Hunt marcasite in Missouri with the map in your pocket

RockHoundR puts these spots on an offline map with BLM and Forest Service overlays, geology layers, and a log for your finds.