Bingham Canyon Mine - a world-class porphyry Cu-Mo-Au locality, notable for display-worthy pyrite on quartz and rare wavellite, prized by collectors.
Key facts
Bingham Canyon is a paradoxical mineral locality: one of the greatest ore bodies ever mined, yet a locality from which fine display specimens are comparatively scarce. Its importance rests first on geology. The mine exposes a giant Eocene porphyry Cu-Mo-Au system centered on the multiphase Bingham stock in the Oquirrh Mountains southwest of Salt Lake City, where monzonite and quartz monzonite porphyry intruded folded Paleozoic quartzite, sandstone, and carbonate rocks of the Oquirrh Group. Around that intrusive center, hydrothermal alteration and mineralization produced a classic zoned system: molybdenite and quartz stockwork in the inner portions, bornite-chalcopyrite-chalcocite-gold mineralization in the high-grade core, chalcopyrite and pyrite outward, and peripheral lead-zinc-silver vein and replacement ores in the surrounding sedimentary rocks.
For collectors, Bingham Canyon is not a “pretty mine” in the usual sense of abundant pocket production. It is a crusher locality, a place where nearly everything was mined for metal rather than saved for cabinets. That is exactly why the best specimens carry such weight. Bingham pyrite on quartz, especially old pieces with bright brassy pyritohedrons, modified cubes, or complex lustrous crystals, has long been the locality’s most recognizable cabinet material. Wavellite and fluorwavellite-related phosphate material from the pit, often pale green, honey, white, or colorless in botryoidal or radiating aggregates, is rarer and more idiosyncratic. Galena, sphalerite, tetrahedrite-group minerals, enargite, quartz, calcite, chalcocite coatings, vivianite, turquoise, molybdenite, and unusual secondary and hydrothermal species round out an assemblage that reflects the full breadth of the porphyry system and its overprinted peripheral ores.
Historically, Bingham Canyon matters because it helped define large-scale open-pit porphyry copper mining. Small underground mines first worked high-grade gold, silver, lead, and copper ores in the nineteenth century, but the district’s transformation came in the early twentieth century, when Utah Copper and Boston Consolidated proved that low-grade disseminated porphyry ore could be mined profitably by steam shovel, rail haulage, and large concentrating mills. The modern pit is the visible monument to that change: an immense terraced excavation cut into a mountain that has yielded copper, molybdenum, gold, silver, and critical-element byproducts for more than a century.
Regional View
Country View
The finest Bingham pieces tend to look unlike specimens from smaller, hand-worked mines. They have an industrial pedigree: isolated crystals or protected seams rescued from ore, old company or geologist collections, labels from the University of Utah or longtime Utah collectors, and occasional specimens tied to named mine levels or zones. A top Bingham specimen is judged as much by survival as by sparkle. Sharp pyrite with clean quartz, undamaged wavellite botryoids on chalcocite-coated quartz, bright galena or sphalerite on matrix, or a well-preserved phosphate specimen from a documented pit level can be a serious Utah cabinet piece even when modest in size.
Photo: Wikimedia Commons
Search for specimens: View all specimens from Bingham Canyon Mine, null
Bingham Canyon Mine is the great open-pit Cu-Au-Mo-Ag operation of the Bingham mining district, Salt Lake County, Utah, on the eastern side of the Oquirrh Mountains. The ore deposit is a porphyry copper system developed around the Bingham stock, a roughly 2 by 2 km multiphase intrusive complex dominated by equigranular monzonite, quartz monzonite porphyry, latite porphyry, and quartz latite porphyry. These intrusions were emplaced into thick Paleozoic siliciclastic and carbonate rocks, and the resulting hydrothermal system produced both the central disseminated-stockwork copper-molybdenum-gold ore and the district’s surrounding skarn, replacement, and vein mineralization.
The porphyry ore body is famous for its zoning. Early actinolite-stable alteration and subsequent biotite, K-feldspar, sericitic, clay, chlorite-epidote, and other alteration styles are distributed around the intrusive center. In the mine’s high-grade portions, bornite, chalcopyrite, chalcocite, and gold were concentrated above and around a barren core; chalcopyrite dominates much of the copper mineralization on the flanks; molybdenite occurs in quartz-molybdenite stockwork veining that continues downward; and pyrite-rich zones fringe the system. Peripheral Pb-Zn-Ag replacement and vein ores, including galena, sphalerite, tetrahedrite-group minerals, and enargite, belonged to the broader Bingham district and, in places, have been incorporated or overprinted by the expanding open pit.
Supergene enrichment was critical to early economic mining at Bingham. Oxidation of pyrite and copper sulfides in the upper parts of the system generated acidic copper-bearing solutions that moved downward and enriched the zone below the leached cap. Chalcocite-rich material with substantially higher copper grades than the primary protore made the low-grade porphyry concept economically compelling in the first decades of open-pit mining.
Mining began in the district with smaller underground operations aimed at higher-grade ores. Gold was recognized early in the canyon, and nineteenth-century work also targeted lead-silver and copper-rich replacement and vein ore. Enos Wall assembled claims over low-grade copper mineralization in monzonite beginning in the late 1880s, and Daniel C. Jackling’s work on the Wall property led to the Utah Copper Company. Samuel Newhouse’s Boston Consolidated Copper & Gold Mining Company worked adjoining ground near Carr Fork and Highland Boy. By 1906, stripping had begun for large-scale open-pit mining, and by 1907–1908 ore was being shipped from the new mechanized operations. Utah Copper and Boston Consolidated were eventually consolidated, and the Bingham operation became the archetype for large-scale open-pit porphyry copper mining.
The mine is operated today by Rio Tinto Kennecott. The integrated operation has included the Bingham Canyon Mine, Copperton concentrator, Garfield smelter, refinery, and associated facilities. Modern public access is through the Rio Tinto Kennecott Visitor Experience, a controlled, ticketed, self-guided overlook and exhibit experience reached by shuttle. Collecting in the pit is not open to the public. Serious specimens in circulation generally come from older saves, mine geologists, company collections, university material, or former district workings consumed by the expanding pit.
Notable specimen production was never routine. Good Bingham material survived because someone was present, recognized it, and removed it before processing. Pyrite-quartz combinations are the classic showy pieces, including lustrous crystals on milky or needle quartz. Wavellite and related phosphate specimens are especially sought when they carry specific mine provenance, such as 8250-foot-level material collected in a small phosphate-rich area, or pale honey wavellite on chalcocite-coated quartz from the northeast quarter of the mine near the base of the Parnell beds. Jerry North’s long association with the mine is important in the modern collector market: specimens from his collection and from other geologist-saved material represent some of the most thoroughly documented Bingham pieces available outside institutional holdings.
Pyrite is the signature display mineral of Bingham Canyon, and the best examples are distinctly different from the massive pyrite one expects in a porphyry system. Collector specimens occur as sharp, lustrous brassy pyritohedrons, modified cubes, and clustered crystals, commonly on milky to clear quartz and in association with tetrahedrite-group minerals, enargite, galena, chalcopyrite, sphalerite, turquoise, vivianite, calcite, or stilbite-group zeolites. Documented specimens range from small thumbnails with single modified crystals around 2.5–4.25 cm across to cabinet clusters about 10 x 6 x 5 cm with individual crystals of roughly 1–2 cm; larger pieces are not common because most crystal-bearing ore was crushed. Fine pieces have bright undulled faces, strong form, intact quartz association, and old or mine-geologist provenance; ordinary pieces tend to be incomplete, oxidized, heavily contacted, or simply massive sulfide with little crystal development.
Chalcocite at Bingham Canyon is more important economically and genetically than as a freestanding display mineral, but collector specimens do exist. Much of the mineral’s significance lies in the supergene-enriched copper ore, where chalcocite replaced or coated earlier sulfides below the leached cap, and in the high-grade hypogene bornite-chalcopyrite-chalcocite-gold zone that has largely been mined away. In hand specimens, Bingham chalcocite is most often seen as dark metallic coatings, seams, disseminated grains, or fracture fillings rather than as abundant discrete crystals; better collector examples include lustrous chalcocite-coated pyrite clusters and the unusual wavellite-on-chalcocite-on-quartz association. Good pieces show a continuous, aesthetically useful black-to-steel-gray chalcocite surface with sharp associated pyrite, quartz, or phosphate mineralization; average material is massive, dull, or ore-only and is valued mainly as locality reference material.
Quartz is the chief stage on which many Bingham specimens perform: milky matrix quartz, clear to white needle quartz, quartz veins, quartzite-hosted material, and quartz-molybdenite stockwork all appear in the locality record. Collector-quality quartz is typically prized when it supports pyrite, tetrahedrite-group minerals, wavellite, faustite, ferrimolybdite, arsenopyrite, molybdenite, galena, sphalerite, or chalcopyrite rather than as isolated quartz crystals. Documented specimens include pyrite on needle quartz, molybdenite crystals to about 8 mm with iron-stained quartz crystals on pieces around 7 cm wide, and phosphate-bearing quartzite pieces carrying white spherical wavellite aggregates. The best quartz specimens from Bingham are clean, open, and undamaged enough to reveal their associated sulfides or phosphates; plain fractured vein quartz without well-exposed accessory minerals is common by comparison and has little cabinet distinction.
Wavellite is one of Bingham Canyon’s most desirable collector minerals because it is rare, visually distinctive, and tied to very specific saves from the pit. It occurs as white, colorless, pale green, honey-yellow, straw-yellow, and brownish botryoidal, spherical, radiating, or acicular aggregates, commonly on quartz, quartzite, chalcocite-coated quartz, or in association with faustite and locally fluorwavellite-composition material. A well-documented 4 x 3.5 x 3.3 cm specimen from the 8250-foot level carried white wavellite spheres on quartz crystals in quartzite from a small phosphate-rich area collected by a mine geologist; other notable material includes pastel-green and straw-yellow botryoids lining boxwork vugs, and pale honey wavellite on chalcocite from the northeast quarter of the mine near the base of the Parnell beds. Better Bingham wavellite is judged by intact rounded aggregates, color contrast against dark chalcocite or quartz matrix, documented mine provenance, and absence of bruising on the soft botryoidal surfaces.
Galena belongs to Bingham’s peripheral and overprinted Pb-Zn-Ag story as well as to the broader set of older district workings that were later affected by the expanding pit. In specimens from the Bingham Canyon Mine locality, it is documented with pyrite, quartz, anglesite, cerussite, turquoise, and sphalerite; old U.S./Lark-related material and Bingham pit pieces commonly show galena as lustrous lead-gray masses, crusts, or crystal faces on skarn or sulfide matrix. Modern collector examples include miniature to small-cabinet pieces around 5 x 3.5 x 3 cm with lustrous galena, sphalerite, and possible tetrahedrite from geologist-saved collections. The better specimens have bright, undamaged galena faces, contrasting matrix, and credible older or mine-geologist provenance; unassuming massive galena without crystal faces can be difficult to distinguish from ordinary district ore unless the label is strong.
Calcite at Bingham Canyon is best understood as an accessory gangue and late vein or cavity mineral in a deposit dominated by sulfides, quartz, alteration minerals, and carbonate-hosted replacement geology. It is documented from the mine, but compared with pyrite, quartz, wavellite, and metallic sulfides, true Bingham calcite specimens are uncommon; market and collection records note only a small number of specimen photos and occasional miniature pieces such as 5 x 4.5 x 4 cm calcite from the Bingham pit. Calcite may occur with sulfides or on altered carbonate/skarn-related matrix, but the locality is not known for large transparent rhombs or classic scalenohedral display pieces. Good Bingham calcite is valued less for perfection of calcite habit than for verified locality, clean preservation, and association with the mine’s sulfide assemblage; unlabeled white carbonate from the district is easy to overvalue or misattribute.
Sphalerite records the zinc-bearing part of the Bingham system, especially the peripheral Pb-Zn-Ag replacement and vein environment around the central porphyry and skarn system. It is documented with pyrite in the mine’s photo associations and with galena and tetrahedrite-group minerals in collector specimens, including modern examples around 4.5 x 2.5 x 2.5 cm with sharp lustrous sphalerite and minor pyrite, and galena-sphalerite pieces around 5 x 3.5 x 3 cm from geologist-saved material. Crystals tend to be dark brown to black, resinous to adamantine when fresh, and more commonly occur as compact crystal groups or lustrous patches than as large isolated transparent crystals. The best examples show sharp edges, good luster, minimal bruising, and clear association with Bingham galena, pyrite, or tetrahedrite-group minerals; ordinary pieces are massive, dark, and hard to appreciate without strong provenance.
Bingham Canyon’s documented mineral list is broad for a porphyry copper district: acanthite, actinolite, andalusite, anglesite, arsenopyrite, azurite, baryte, bismuthinite, bornite, brochantite, calaverite, cerussite, chalcanthite, chalcopyrite, chrysocolla, covellite, cuprite, digenite, diopside, dolomite, enargite, epidote, faustite, ferrimolybdite, fluorite, fluorwavellite, foshagite, tetrahedrite/freibergite-group minerals, garnet-group minerals, goethite, grossular, gypsum, gyrolite, hematite including specularite, hemimorphite, hessite, jamesonite, jarosite, kaolinite, magnetite, malachite, marcasite, mawsonite, melanterite, molybdenite, montmorillonite, muscovite/sericite, native copper, native gold/electrum, native palladium, native platinum, native silver, nontronite, nukundamite, okenite, orpiment, pentlandite, petzite, pyrrhotite, realgar, rhodochrosite, rhodonite, roquesite, siderite, smithsonite, stannite, stibnite, talnakhite, tenorite, thaumasite, thomsonite-Ca, tobermorite, turquoise, vivianite, wittichenite, and wollastonite among others. The mine is particularly interesting for rare hydrothermal and secondary species such as fluorwavellite, foshagite, okenite, gyrolite, thaumasite, thomsonite-Ca, tobermorite, and telluride/sulfosalt-bearing ore-mineral assemblages. In the broader Bingham district, the Lucky Boy mine is historically tied to mallardite, but collectors should not transfer that type-locality significance automatically to Bingham Canyon Mine labels.
Bingham Canyon specimens should be bought with provenance in mind. The locality is huge, old, and surrounded by many named district workings, several of which have been physically altered, absorbed, or obscured by the growth of the pit. Labels may say “Bingham,” “Bingham Canyon,” “Bingham Copper Mine,” “Kennecott,” “Utah Copper Mine,” “Bingham pit,” or the name of an older mine such as U.S./Lark. Some of these labels are historically meaningful, but they are not always mineralogically equivalent. A specimen from the Bingham mining district is not automatically from the open pit, and a piece from an old Pb-Zn-Ag mine later consumed by the pit should be preserved with exactly that history rather than flattened into a generic Bingham Canyon attribution.
The most common authenticity issue is not deliberate fakery but over-broad labeling. Pyrite on quartz from Bingham has a particular cachet, and bright pyrite-quartz combinations from other localities can be mistakenly or optimistically assigned to it. Ask for old labels, mine-geologist provenance, collection history, or a chain of ownership when paying a premium. Wavellite and fluorwavellite-related material require extra care because wavellite from other localities is far more abundant; Bingham pieces with specific mine level, zone, or collection data are much more desirable than generic “Bingham” wavellite.
Condition matters severely. Pyrite crystals are often contacted, chipped, or dulled; quartz needles are easily broken; wavellite botryoids bruise and abrade; chalcocite coatings can be soft-looking, tarnished, or rubbed; sphalerite and galena edges chip; and calcite may be cleaved or etched. Many Bingham pieces were extracted from production settings rather than specimen pockets, so some contact is acceptable, but sharp, unrepaired, well-composed specimens command a strong premium.
Handling considerations are mostly practical. Keep sulfide-rich specimens dry and stable; avoid humid storage, especially for pieces containing pyrite, marcasite, melanterite, chalcanthite, or other alteration-prone sulfates. Wash nothing aggressively. Chalcocite coatings, soft phosphate aggregates, and delicate quartz sprays should be dusted only with a soft brush or air bulb. Fluorescence is not the main attraction of Bingham material, though individual calcite or secondary minerals may respond weakly depending on composition; do not value Bingham specimens primarily on that basis unless a specific response is demonstrated.
Market availability is limited but not nonexistent. Pyrite-quartz pieces appear most often, followed by occasional wavellite, chalcocite-coated pyrite, galena-sphalerite, quartz-molybdenite, and reference ore specimens. The best pieces usually come from old Utah collections, university deaccessions, mine geologists, or named collections such as Jerry North-related material. Because the mine is active and access is controlled, do not expect new public collecting. The supply is essentially the supply that was saved.
Bingham Canyon’s collector story begins with a kind of geological misdirection. The ground that became one of the world’s great copper mines did not look like treasure in the way nineteenth-century miners expected. Prospectors wanted rich veins and obvious ore; the future of Bingham lay in vast volumes of dull, low-grade, leached monzonite. Enos Wall noticed copper oxide staining in the canyon walls and patiently assembled a large block of claims over weakly mineralized rock beginning in the late 1880s. To many mine promoters, it was too lean to matter. To Daniel C. Jackling, it was a metallurgical problem waiting for the right scale. When Jackling took control of the Wall property in 1903 for Spencer Penrose and Charles MacNeill, the idea was audacious: move a mountain, mill the rock in bulk, and make money not by finding spectacular ore shoots but by making low-grade copper ore behave like an industrial raw material.
Samuel Newhouse’s part of the story has the feel of frontier capitalism at high speed. He had already made a success of the Highland Boy mine, then acquired the Steward claims in Carr Fork. His Boston associates judged the original 27-acre property too small for a major promotion, so Newhouse sent instructions to acquire the open ground between the Steward property and Enos Wall’s claims. That added more than 300 acres, much of it over a barren-looking hill of leached monzonite. The “barren” hill turned out to cover much of the Bingham Canyon copper ore body. What looked like promotional acreage became one of the most consequential patches of mining ground in American history.
The first years of open-pit work were not graceful. Steam shovels and trains replaced candlelit stopes and mule trams, but the ore body made its own rules. Stripping began in June 1906 at Boston Consolidated and in August 1906 at Utah Copper. Utah Copper had expected to move quickly, but a thinner leached cap in the canyon bottom and a troublesome high-pyrite zone higher on the mountain complicated the plan. Even so, Utah Copper shipped open-pit copper ore in June 1907, and Boston Consolidated followed in January 1908. By 1910, financial pressure and geology had pushed the adjoining operations toward consolidation. The result was a single expanding excavation that eventually swallowed claims, workings, roads, communities, and collecting localities into one enormous terraced pit.
For specimen collectors, one of the most evocative stories is not about a spectacular pocket but about a single childhood gift. A collector on Mindat described receiving a Bingham pyrite from his grandfather at age ten or eleven; the grandfather had acquired it from an uncle who ran the Highland Boy Stamp Mill near the top of Bingham Canyon. That one brassy piece from the growing open-pit copper mine “piqued” the young collector’s interest in minerals. It is a small episode, but it captures why Bingham pyrite matters. These specimens were not mined by the flat for showrooms. They passed through families, mills, mine offices, and geologists’ hands, each survival a narrow escape from the ore stream.
The 2013 Manefay landslides turned the pit itself into a geologic event. On April 10, two massive rock avalanches began in the northeast corner of the open pit. The first, at 9:30 p.m., carried nearly 100 million tons of material; the second followed a little more than an hour and a half later. In all, about 145 million tons of waste rock moved into the pit bottom. The slide mass dropped roughly 2,975 feet along a path about 9,840 feet long from a headwall about 1,150 feet high. Instead of behaving like an ordinary slump, the mass flowed as a rock avalanche, reaching speeds greater than 70 mph. Eleven minutes after the second slide, a small earthquake of about magnitude 2.5 shook beneath the mine, triggered by the rapid shift in load.
The remarkable part is what did not happen. No one was killed or injured. Mine monitoring had shown instability beginning in November 2012, with movement becoming more threatening in early 2013. On April 10, the slope was moving at about 2 inches per day; employees were evacuated at 11 a.m., and a press release warned that a slide was imminent at 2:38 p.m. The slide still destroyed or damaged major infrastructure and equipment: 3 of 13 shovels, 14 of 100 haul trucks, and additional drills, bulldozers, and graders. Haul trucks were approximately $5 million machines, and shovels about $45 million each. Ore production resumed just 17 days later because the in-pit crusher and underground conveyor were not destroyed. Rebuilding the haul road required a new road about three-quarters of a mile long and 150 feet wide, cut through roughly 6 million tons of landslide debris, with more than 20 pieces of remote-controlled heavy equipment working where it was not yet safe for people to go.
There is a quieter modern collecting story in the work of mine geologists. A few of the best recent-market Bingham specimens are associated with people who understood both the geology and the fleeting opportunity. Wavellite from the 8250-foot level was collected from a small phosphate-rich area by a mine geologist and later reached collectors through Gerry Austin. Jerry North, who worked as a geologist at Bingham Canyon Mine for two decades, was tasked while employed by Kennecott with collecting mineral specimens for the company collection. In the process he assembled a remarkably comprehensive private collection from a locality that, despite its size, rarely releases good specimens. In a mine that moves rock on a scale almost beyond mineral-collector imagination, the survival of a 5 cm wavellite, a chalcocite-coated pyrite, or a sharp sphalerite miniature can feel nearly miraculous.
