Cookes Peak District
Deposit type & geology
Carbonate-hosted polymetallic replacement (Pb-Zn-Ag-Cu, with Au).
Fusselman Dolomite and Percha Shale (limestone units), intruded by the Cookes Peak Granodiorite; also diorite.
Age: Cookes Peak Granodiorite stock ~38.8 ± 1.1 Ma (K-Ar, Loring & Loring 1980) — latest Eocene/earliest Oligocene.
Structural geology & terrain
Vein/structure orientation: Replacement bodies localized at the junction of N15°W/NNW-striking faults with N55–65°E-striking faults
Named controlling structure: No individually named fault identified in sources reviewed — structural control is the fault-junction pattern itself, capped by an impermeable shale
Elevation range: 8,404 ft (Cookes Peak summit) — highest point in the Cookes Range
Prominent, steep desert range rising sharply from the Deming plains; visible for great distances, historically used as a landmark on the Butterfield Overland Trail.
High-resolution terrain
~6 m/pixel lidar-derived hillshade (USGS 3DEP) — fine enough to reveal old mine workings, waste-rock piles, trenches, and roads the statewide terrain layer can’t show. Toggling to a different district turns this off.
Historical production
$4,200,000 combined district value, 1876–1965 (NMBGMR RM-24, citing North & McLemore) — gold is a listed commodity (with Cu, Ag, Pb, U, Ba, Fe) but not separately itemized in ounces in any source found. One of Luna County's principal historic producing districts, distinct from the nearby Tres Hermanas and Victorio districts.
Sources: NMBGMR RM-24 (McLemore, DIS105); NMBGMR Bulletin 72 (Griswold 1961); NMBGMR Bulletin 37 (Jicha 1954); USGS Professional Paper 68 (Lindgren, Graton & Gordon 1910); USGS MRDS (Desdemona Group record); BLM New Mexico (2021 safeguarding project); Wikipedia (Cookes Range, cross-checked) researched — see sources
Current status
Inactive as a producer. BLM and NM EMNRD completed a multi-year (2014–2021) abandoned-mine safeguarding project remediating 300 dangerous openings on BLM-managed land around the peak. No current mining or exploration activity identified.
Dormant — no recent activity
BLM New Mexico and NM EMNRD completed the final phase of an abandoned-mine safeguarding project in 2021 (300 dangerous mine openings remediated 2014–2021) — a safety/reclamation project, not new mining or exploration.
Land ownership & directions
Federal public land administered by the Bureau of Land Management — generally open to mineral entry under the 1872 Mining Law, subject to staking and permitting rules.
BLM-managed (Cookes Peak summit and much of the Cookes Range); the range includes the Cooke's Range Wilderness Study Area. Cookes Range, Luna County, north of Deming; unpaved roads, WSA status limits vehicle access in parts of the range.
See specimen photos (mindat.org) → — this app doesn’t host specimen photos itself; this searches mindat.org’s own mineral-specimen database, which isn’t necessarily specific to this exact district.
This pin is a generalized district/historic-site reference point, not a surveyed claim boundary — routes may cross private or patented inholdings where public access isn’t guaranteed even if a road reaches the site. Backcountry mine areas commonly have unmarked shafts, unstable ground, and no cell service; confirm current access and safety conditions (land manager, county, or landowner) before heading out.
Tailings reprocessing potential
Historic processing method and mill scale not established in the sources reviewed this session, despite substantial documented production ($4.2M combined value district-wide).
This is a documentary heuristic, not assay data.The tier above is inferred from historic production era, processing method, and ore character already cited elsewhere on this page — nobody has sampled or assayed this district’s tailings as part of this research. Actual recoverable gold content can only be established by physical sampling.
Reprocessing tailings is regulated mining. Disturbing or reprocessing historic mill waste requires the same NM Mining Act permitting as new mining (see the regulatory companion guide), regardless of who currently holds the claim or surface rights — and ownership of the tailings material itself is a separate legal question from mineral rights on the underlying land.
Legacy tailings can be hazardous. Pre-modern processing commonly used mercury (amalgamation) or cyanide (heap leach), and can carry elevated arsenic and other heavy metals — not a casual sampling target, and disturbing contaminated material can carry real environmental liability.
Geologist’s read
Added this session after an MRDS spatial sweep flagged it as a high-confidence major district not on the original map. The replacement ore here is structurally controlled in a documented, textbook way (per the MRDS record for the Desdemona Group): faults striking N15°W and NNW, at their junctions with faults striking N55–65°E, beneath an impermeable shale cap — a clean example of the same carbonate-replacement style seen at Chloride Flat and Victorio elsewhere on this map.