Deposit

Southwestern Graphite

Southwestern Graphite is a graphite deposit in Texas with published resource estimates, recorded in the USGS USMIN mineral deposit database from the 2022 graphite deposits data release.

Facts on this page last re-verified Aug 13, 2026 — the oldest verification date among its current claims. How we verify.

Location: Texas, United States (30.786, -98.356 approx.)

Commodities: graphite

Deposit model: 37f - Disseminated flake graphite

Geology

USGS records this site as hosted by micaceous quartzite, injection gneiss, quartz-mica schist of the Packsaddle schist (Precambrian), with disseminated mineralization. (Cameron and Weis (1960))

Published resource estimates

As compiled by USGS USMIN from the cited studies. Resource classes follow the source; "approximate" flags values USMIN reports as approximations. These are not current company reserve statements.

Material	Class	Amount	Grade	Contained	As of	Reference
graphite	Unclassified	800,000 t	5.2 percent	42,000 metric tons graphite	Jan 1, 1987	Fogg and Boyle (1987), Page 20 — Fogg, C.T., and Boyle, E.H., Jr., 1987, Flake and high-crystalline graphite availability–Market economy countries—A minerals availability appraisal: U.S. Bureau of Mines Information Circular 9122, 40 p.

Recorded production

Southwestern Graphite, Southwestern Graphite mine: produced 75,000 metric tons of graphite, 1937–1979 (Fogg and Boyle (1987), Page 20 — Fogg, C.T., and Boyle, E.H., Jr., 1987, Flake and high-crystalline graphite availability–Market economy countries—A minerals availability appraisal: U.S. Bureau of Mines Information Circular 9122, 40 p.)

Exploration and site history

Active — Property initially worked in 1913 with intermittent operations to 1937, then continuous production from 1937–1979 (1), 1913–1979 (Cameron and Weis (1960))
Evaluation — Deposit was evaluated to determine remaining graphite, 1928 (Cameron and Weis (1960))

Record imported from USGS USMIN ver. 4.0 (June 2019). Developments after that date appear on facility records, not here; see the methodology.

Sources

U.S. Geological Survey · published Jan 1, 2022 · retrieved Aug 13, 2026 · archive unavailable: archive.org has been unreachable since 2026-08-12, so no Wayback snapshot could be captured for this record; recheck on a weekly pass
U.S. Geological Survey · published Jan 1, 2022 · retrieved Aug 13, 2026 · archive unavailable: archive.org has been unreachable since 2026-08-12, so no Wayback snapshot could be captured for this record; recheck on a weekly pass