1. La Grange area, Lewis County: Lake Superior agates and jasper in gravel pit spoil piles.
2. Kahoka – Wayland – Alexandria area, Clark County: Keokuk-type quartz geodes weather out of the
Warsaw and Keokuk formations (Misissippian); some geodes also contain calcite, dolomite, pyrite or
other accessory minerals.
3. Washington County, especially in the vicinity of Potosi, Old Mines, Cadet, Mineral Point and Richwoods: drusy quartz (Missouri lace agate), bladed barite, and limonite abundant, galena much less common, in red clay residuum of the many abandoned open-pit barite “tiff” mines.
4. Joplin – Webb City – Oronogo area, Jasper County (Missouri part of world-famous Tri-State Zinc district): pink dolomite, calcite, sphalerite, chalcopyrite, and more rarely galena on the many abandoned mine dumps.
5. Silver Mines area, about eight miles west of Fredericktown, Madison County: argentiferous galena, sphalerite, wolframite (uncommon), pyrite, arsenopyrite, fluorite, and a host of other high-temperature accessory minerals in vein quartz on mine dumps. One-half mile by trail upstream from state Route D bridge over the St. Francis River.
6. Mexico area, Audrain County: clusters of small pyrite crystals in the abandoned fire-clay pits
piles.
7. Southeast Missouri, especially Carter, Wayne, Howell, Oregon, Ripley and Butler counties: limonite
(mammillary, box-work, and “pipe-ore” masses), common in the many abandoned open pit iron of this region.
8. Lincoln, about 10 miles north of Warsaw, Benton County: residual masses of “mozarkite” (red/
mottled chert), the Missouri state rock are found in road ditches, creeks, excavations, etc.