Tri-State district
mine in United States of America
The Tri-State district was a historic lead-zinc mining district located in present-day southwest Missouri, southeast Kansas and northeast Oklahoma. The district produced lead and zinc for over 100 years. Production began in the 1850s and 1860s in the Joplin - Granby area of Jasper and Newton counties of southwest Missouri. Production was particularly high during the World War I era and continued after World War II, but with declining activity. As jobs left the area, the communities declined in population.
The Picher, Oklahoma mines were finally closed in 1967, and the "Swalley" mine near Baxter Springs, Kansas in 1970. Because of extensive toxic environmental wastes produced from these lead and zinc deposits, known as chat, large areas have been rendered uninhabitable and damage has been caused to air, land and water quality. In some areas, such as Picher, Oklahoma, the federal government bought out the last inhabitants and the town was disincorporated in 2013.
Three large sites in this district have been classified by the Environmental Protection Agency as mining-related Superfund sites: the Tar Creek Superfund site in northeast Oklahoma; the Jasper County and Newton County sites in southwest Missouri; and the Cherokee County site in southeast Kansas. In 2019 EPA announced a plan for continued funding of $16 million annually for cleanup at Tar Creek.
Begin with the source’s own compact description: “Tri-State district” is mine in United States of America. The dossier treats that line as a proposition to test through Tri-State, district and mine, not as a finished interpretation.
Why this record matters
The phrase “mine in United States of America” supplies a clear boundary for inquiry. It also exposes the unanswered questions: who defined that boundary, when it became stable and which sources sit outside it.
The citation trail is more important than the brevity of the summary: it shows where individual claims can be examined in context. The source revision retrieved here is dated Jun 27, 2026. The linked authority identifier is Q7839763. VIAF identifies the subject as 156315828. The Library of Congress control number is no2007053141. Authority coordinates are 37.000, -94.500. 1 of 3 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1967, 1970, 2013 and 2019.
The absence of detail may reflect summary conventions rather than a lack of surviving documentation. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.
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This entry incorporates text from “Tri-State district” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.