Rowley Mine wulfenite is a connoisseur’s Arizona classic: bright orange to honey-yellow PbMoO4 in glassy tabular blades, often perched on white to iron-stained baryte and sharpened visually by red-orange to yellow mimetite. The finest pieces have the unmistakable “Rowley look”—thin, transparent, square to rectangular plates with beveled edges, sometimes so clear that collectors call them windowpanes, with sprays, balls, or drusy fields of mimetite around or upon them.
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The mine sits on the western edge of the Painted Rock Mountains in Maricopa County, northwest of Gila Bend and near Theba. It began as a small but ambitious copper-lead-gold-silver-molybdenum-vanadium-baryte-fluorspar prospect, yet its lasting importance has been mineralogical rather than industrial. The Rowley vein is a fault-controlled system in Tertiary volcanic rocks, with a quartz-rich footwall vein and a thick baryte-rich hanging-wall vein. That baryte mass became the stage on which later oxidation assembled the wulfenite-mimetite suite collectors prize today.
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The appeal is not simply color. Rowley’s best wulfenites combine delicacy, transparency, geometry, and contrast in a way that differs from the more massive red-orange plates of some other Arizona localities. Many are small by world standards, but they can be exquisite: freestanding blades on baryte, clusters of orange glass on porphyritic matrix, or wulfenite partly ornamented by “wet-looking” mimetite balls. The locality also matters historically. It has been known to Arizona collectors for decades, was treated in early and modern mineralogical literature, and is now recognized as a remarkably complex mineral locality, including a growing suite of rare and type-locality post-mining minerals related in part to bat-guano chemistry.
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For collectors, a good Rowley wulfenite is judged first by intactness and luster. The crystals are commonly thin; tiny edge bruises, missing corners, and rehealed-looking contacts are common. The best specimens show sharp, complete plates with high vitreous luster, saturated orange to butterscotch color, and a coherent display on baryte or contrasting dark matrix. Red mimetite balls are a premium association, especially when they sit naturally on clear orange wulfenite without obscuring it.
Search for specimens: View all wulfenite specimens from Rowley Mine, Arizona, USA
The Rowley Mine is in the Painted Rock Mining District on the western edge of the Painted Rock Mountains, Maricopa County, Arizona, roughly northwest of Gila Bend and near the small settlement of Theba. Historical names include Rawley Mine, Reliance Mine, Reliance Copper Mine, Rainbow Mine, Theba Mine, and the San Carlos patented claim. It is a mine, not an open collecting area; the property is private, and collecting or entering underground workings requires permission from the leaseholders or operators.
The deposit is a fault-controlled vein system hosted by Tertiary volcanic rocks, especially andesite flows, with rhyolitic volcanic rocks noted regionally and later basalt cover in the district. The Rowley vein follows a northwest-striking fault zone. Mineralization is divided into two adjoining veins in the same structure: a massive quartz-rich footwall vein and a baryte-rich hanging-wall vein. The quartz portion is described as several feet wide in the main shaft and on the 125-foot level; it carries massive quartz, minor jasper, specular hematite, sparse pyrite, and bands or fracture coatings of malachite and chrysocolla. The baryte vein is much thicker, locally on the order of tens of feet, and contains baryte with galena, calcite, wulfenite, vanadinite, copper oxide staining, and a broad suite of secondary lead-copper minerals.
Mining began after discovery around 1900 and became organized with the Rowley Copper Mines Co., incorporated in 1909. A small camp developed at the site, including a bunkhouse, boarding house, cottages, tents, and power houses. Water was a persistent enemy: early accounts describe Cornish pumps running 16 hours a day and lifting 200 gallons per minute to keep workings from flooding. A 75-ton concentrator was built in 1917, after wulfenite had been found, to treat ore from the mine. In 1922 the Reliance Copper Co. succeeded the Rowley company, but operations soon stalled; foreclosure followed, and Charles A. Rowley became majority owner and president of Rowley Mines, Inc. in 1927.
The mine’s metal production was modest. Historical accounts record intermittent exploitation from 1909 to 1923 for copper, lead, molybdenum, gold, and related values. A USGS account notes that perhaps 8,000 to 10,000 tons of vein material were mined during development, with at least 2,000 tons milled. Shipments included a small car of copper ore averaging 15 percent copper and 30 tons of wulfenite concentrate containing 18.26 percent MoO3. By 1933, a report described more than 1,400 feet of development and ore shipments valued at $10,000, but groundwater and poor depth results discouraged sustained expansion.
The workings include inclined shafts, a vertical shaft, drifts, crosscuts, and stopes. The main inclined shaft, the Jobes or Jones shaft, and the 125-foot level recur in descriptions of the mine. The 125-foot level is especially important in modern mineralogy: many unusual post-mining minerals, including several type-locality species, have been documented there in a guano-influenced environment.
Specimen collecting transformed the mine’s reputation. For much of the twentieth century, Rowley was a known Arizona collector locality, and many collectors prized its orange wulfenite and mimetite long after ore mining had ceased. Later, more organized specimen recovery under claim control produced additional fine material. Lower levels have been affected by flooding and access restrictions, and underground conditions have long been hazardous because of fractured baryte, old timbering, collapses, and the aftereffects of fire and decades of collecting pressure. Surface-dump collecting has produced micromount and thumbnail material when done with permission, but the mine should be treated as a private, dangerous, controlled locality rather than a recreational rockhounding site.
Rowley wulfenite is most famous for lustrous tabular crystals in orange, golden-yellow, honey, butterscotch, and red-orange tones. The classic habit is a thin tetragonal plate, commonly square or rectangular, with beveled edges and a vitreous to glassy luster. Good examples may be gemmy enough to transmit light through the crystal, especially along thinner margins. Some crystals show a “windowpane” appearance: broad, flat, transparent plates with sharp edges and glowing orange color.
Crystal size is usually modest. Many crystals are a few millimeters across; attractive thumbnails and miniatures commonly show plates in the 5–10 mm range. Crystals around 1 cm are desirable, and crystals approaching 2 cm on edge are large for the mine. Mindat’s locality data records excellent crystals to 2 cm on edge, which fits the upper range seen in published and photographed specimens.
The most characteristic association is mimetite, Pb5(AsO4)3Cl. At Rowley, mimetite can form tiny drusy coatings, orange to yellow “rice grain” aggregates, sheaves, hexagonal prisms, and red to orange spherules. The most prized combination is transparent orange wulfenite with deep red, wet-looking mimetite balls. The mimetite may decorate the wulfenite, partly cover it, or form a colorful base beneath the plates. When the mimetite enhances rather than hides the wulfenite, the specimen takes on the bold, instantly recognizable Rowley style.
Baryte, BaSO4, is the most important matrix and gangue for many specimens. Rowley baryte may be white, gray-white, brownish, or iron-stained, commonly bladed or massive. Wulfenite on bladed baryte can be highly aesthetic because the orange plates stand against a pale, textured ground. Some specimens sit on darker porphyritic volcanic matrix, where the contrast is different but equally attractive. Quartz, chalcedony, chrysocolla, malachite, cerussite, anglesite, galena, vanadinite, descloizite, fluorite, calcite, caledonite, linarite, leadhillite, phosgenite, boleite, and other secondary species are part of the broader Rowley mineral system.
The Rowley palette can overlap with other Arizona wulfenite localities, but the texture is distinctive. Red Cloud wulfenite is famous for deep red plates; Glove Mine material often has thicker orange to reddish plates on limonitic matrix; Rowley is more often about smaller, very glassy, orange to butterscotch tabular crystals with mimetite and baryte. Fine Rowley specimens reward close viewing: one looks for crisp edges, transparency, beveled faces, freestanding blades, and the delicate spatial relationship between wulfenite and mimetite.
Quality factors are unforgiving. The crystals’ thinness makes pristine edges rare. A great Rowley piece should have several complete blades, minimal broken corners, strong luster, good color saturation, and a natural display angle. Matrix is a plus when it protects the crystals and gives contrast. Loose single plates can be dramatic, but matrix specimens are more stable and generally more desirable when the composition is balanced.
Rowley Mine wulfenite is available, but fine pieces are not common. The market contains a mixture of older collection specimens, pieces from organized collecting periods, dealer stock, and small modern thumbnails. Ordinary examples with small orange blades appear regularly; truly sharp, transparent, damage-free crystals on aesthetic baryte or with premium red mimetite are much harder to secure.
Condition is the central issue. Wulfenite has perfect to distinct cleavage and Rowley crystals are often thin plates; edge chipping is extremely common. Under magnification, look at the corners and blade edges first. Check whether the apparent “growth irregularities” are natural stepped edges or actual impact bruises. Pay attention to contacts where crystals meet matrix or other blades, and be wary of display lighting that hides broken margins. A few inconspicuous edge nicks may be acceptable on a rare or highly aesthetic piece, but significant missing corners sharply reduce value.
Authenticity concerns are mostly provenance and condition rather than known Rowley-specific treatments. No well-established Rowley wulfenite fakery tradition is part of the standard mineral literature, but mislabeling can occur because many Arizona wulfenites are orange, tabular, and superficially similar. A genuine Rowley label should be consistent with the mine’s style: orange to yellow glassy tabular plates, commonly with baryte and mimetite, and often smaller than comparable showy pieces from some other famous Arizona mines. Old labels from Arizona collectors, recognized dealers, or collections documented in The Mineralogical Record are especially valuable.
Mimetite associations require close inspection. On the best natural pieces, mimetite is integrated with the growth surfaces and cavities, not randomly sprinkled. Red to orange mimetite balls on wulfenite are highly sought after, but heavy mimetite coverage can obscure broken wulfenite or make the species balance less attractive. Vanadinite after wulfenite from Rowley is a separate collecting subtheme: these pseudomorphic or replacement-style pieces can preserve wulfenite shapes coated or replaced by reddish-brown to orange vanadinite.
Cleaning should be conservative. The appeal of Rowley material depends on luster and sharpness, and aggressive cleaning can loosen thin plates, detach mimetite, or brighten matrix in a way that looks unnatural. Avoid ultrasonic cleaning for delicate specimens. Handle by the matrix, not by crystal edges, and mount valuable thumbnails or miniatures in a perky box or custom base to prevent vibration and finger contact.
Because the property is private and hazardous, specimens with legitimate provenance matter. Do not treat Rowley as a casual collecting destination. Permission, safety control, and claimholder rights are central to the locality’s modern status.
At first glance, Rowley’s desert setting seems too severe for a locality famous for glassy orange mineral beauty. The mine is perched roughly 800 feet up the west slope of a Painted Rock Mountains hillside, far from the polish of a museum case. Yet the place was never merely a collector’s hole in the ground. In the early boom years, a small camp grew around it: bunkhouse, boarding house, cottages, tents, power houses, and the machinery needed to keep a stubborn wet mine alive in the Arizona desert.
Water was one of the mine’s defining adversaries. The workings demanded Cornish pumps running 16 hours a day, lifting 200 gallons of water per minute. For a mine now remembered for delicate wulfenite plates, it is a striking image: underground men chasing copper, lead, gold, and molybdenum while a mechanical heart pumped thousands upon thousands of gallons from the workings simply to keep the ore accessible.
The protective streak around the property became part of the story after Charles A. Rowley acquired the mine as majority owner in 1927. Rowley was not casual about his holding. He hired a night watchman and sealed the site with a 6-foot barbed-wire fence embedded in concrete. That image—barbed wire fixed in concrete around a mineral locality—feels severe, but it says something important about the mine’s perceived value and the problem of unauthorized entry even before wulfenite collecting became the mine’s primary fame.
By 1933 the operation had more than 1,462 feet of workings, including inclined shafts, a vertical shaft, and hundreds of feet of drifts and crosscuts. That year, recorded ore shipments reached $10,000. But the mine was never able to escape the combined pressure of water, difficult ore values, and complex underground conditions. Diamond drilling found no encouraging improvement at 360 feet, and another drill hole at 290 feet failed to show better ore grade. The mine’s industrial promise faded, while its mineralogical importance was still waiting to be fully understood.
The underground setting that made specimens possible also made collecting dangerous. The ore body was in fractured baryte, and the baryte ground was unstable enough to command caution even when timbering was in place. A 1971 report recorded that vandals had started a fire that destroyed timbering in the incline shaft, making underground collecting still more formidable. Later collecting enlarged pockets and altered cavities in places, leaving an underground landscape shaped by both mining and the pursuit of specimens.
Among the most memorable collecting stories belongs to Monnie Speck’s famous pocket. The Rowley specimens collectors now revere—orange wulfenite with deep red, wet-looking mimetite balls—owe much of their mystique to those finds. A 6.2 cm wulfenite-mimetite specimen from the Susie Davis collection, probably collected by Monnie Speck, became one of the most famous Rowley pieces. It was sold to the Smithsonian Institution in 1972 with the rest of Davis’s collection and later photographed by Rock Currier in 1973. Another 7.2 cm specimen from the same famous pocket, wulfenite and wet-looking mimetite on baryte, was in Wayne Thompson’s collection when Currier photographed it in 1973. Those pieces helped fix the ideal Rowley image in collectors’ minds: clear orange plates and glistening red mimetite, compact but unforgettable.
One stope gained a name that sounds almost too poetic for a mine: the “blue room.” It was so called because chrysocolla lined the walls. In a deposit celebrated for orange and red minerals, that blue chamber adds another layer to Rowley’s character. The mine is not just a wulfenite locality; it is a supergene color laboratory where lead, copper, molybdenum, vanadium, arsenic, sulfate, carbonate, chloride, and even guano-related chemistry created sharply different mineral zones.
A modern twist came from the Rowley Mine’s post-mining mineralogy. Researchers working on material from the 125-foot level found an unusual bat-guano-related assemblage that produced a series of new minerals. Edwindavisite was named for F. Edwin Davis, Jr., the Arizona-based mineral collector and contractor operator of the mine, credited with helping provide access, assisting exploration, and removing specimens from difficult underground workings. In a locality already famous for classic wulfenite, the mine acquired a second identity as a scientific locality for rare ammonium, oxalate, phosphate, and related species formed in the peculiar chemistry of an abandoned mine environment.
Amethyst
Quartz
Fluorite
Tourmaline
Malachite
Azurite
Rhodochrosite
