Mineral Record: The Purple Passion Mine
INTRODUCTION
The Purple Passion mine (originally known as the Diamond Joe mine) is located approximately 8 miles northeast of Wickenburg, Arizona (about 60 miles west and a little north of Phoenix). In addition to the usual tabular wulfenite crystal shape, the Purple Passion mine produces several very odd crystal habits of wulfenite such as acicular (needles) and epitaxial needle growth over tabular crystals ("fuzzy tabs"). The wulfenite displays many colors and also occurs on a wide variety of matrices, such as wulfenite on quartz (clear, smoky, milky and amethyst) and wulfenite on fluorite, calcite or galena. Other associations include anglesite, cerussite, sulfur, chlorargyrite, smithsonite and willemite. In addition to the odd associations, some of the specimens of calcite, fluorite, wulfenite and willemite are strongly fluorescent.
Through the years, the surrounding property has occasionally yielded small quantities of minerals and current activity is producing a fair amount of good quality wulfenite specimens. The mine consists of two unpatented claims on government land (controlled by the Bureau of Land Management) in the White Picacho mining district, in Yavapai County, Arizona.
The mountains around Wickenburg have been extensively mined for gold, silver, lead and molybdenum, so it is common to see tailings piles and adits in the general area on the way to the mine. In addition to many small prospect sites, the King Solomon, Octave and Monte Cristo mines are located to the north; to the southeast are the Great Southern and the Monarch mines. The Purple Passion mine is not specifically named in Mineralogy of Arizona by Anthony et al. (1975), but it is mentioned as follows: [wulfenite occurs] "at a prospect near the Great Southern mine, as tabular to unusual fibrous crystals with fluorite."
LOCATION AND CLIMATE
The Purple Passion mine is in the Wickenburg Mountains located on the USGS Arizona Morgan Butte 7.5-minute topographical map at T8N R3W, SEC 30, SE 1/4; the latitude is N34° 0' 2" and the longitude is W112° 35' 53". The mine is in the Sonoran Desert, about 3,300 feet above sea level. At this elevation, the desert climate is somewhat milder than in the lower desert, but during the three summer months, daytime temperatures routinely climb above 110°F making it almost unbearable for the casual mineral collector. The winter temperatures get down to freezing on some nights. The average rainfall is about 6 inches yearly.
On the way to the mine we have seen a variety of desert animals including rabbits, range cattle, three deer, a coyote, many birds, a gopher snake, several rattlesnakes, a javelina, scorpions, tarantulas, honey bees, lizards and a gila monster. Two diamondback rattlesnakes appeared at our tailings pile and they currently live about 40-50 feet down one of the old vertical shafts.
Panoramic image of the Purple Passion Mine near Wickenburg, Arizona. Image by: Mark Mauthner, September 2015.
HISTORY
Late in the fall of 1995, Ed and I got together with four other mineral collectors (John "Mac" McClelland, Gaylord "Jay" Hayes, Gary Spraggins and Scott McCloed) to actively work a site that Jay knew about. On the surface we saw a vein of material which consisted of small wulfenite crystals in calcite with an occasional thin vein of fluorite or galena. Along the base of the hill, about 100 feet south of a small pile of purple tailings, there is an inclined shaft, a vertical shaft, a windmill-powered water pump, two water tanks, an old forge and some small concrete bases for a winch system. The vertical shaft is about 15 to 20 feet in diameter and goes straight down approximately 45 to 50 feet. There does not appear to be any significant mineralization in the vertical shaft.
The inclined shaft follows the vein down at about a 550 angle toward the vertical shaft. It is about 6 feet square and is collapsed after the first 15 feet. The vein exposed in this inclined shaft is mostly calcite containing small layers of green fluorite with traces of galena and wulfenite. Across the wash and up a hill, about 500 feet to the southwest is another vertical shaft and some major concrete foundations (this shaft is collapsed about 20 feet down). Only a small amount of tailings are present at any of these locations and we originally believed the whole site must have been either a millsite for trucked in material, or just prospect holes with no major workings, but this was not the case. Conversations with some mineral collectors turned up rumors that a series of tunnels once existed at the site but that the tunnels were now caved in.
An old concrete base that was once used for a winch system. Image by: James Horste, September 2015.
The vertical shaft is approximately 15 to 20 feet in diameter and has a depth of 50 feet. Image by: James Horste, September 2015.
We eventually located Bill Hunt, a micromount collector with some first-hand knowledge of the site. Bill came up to the mine in the middle of May (1996), and shared with us what he remembered about the site. The mineralized vein lays on a fault surface of a hill which extends above the wash. Around 1975, Bill Hunt (and some of his friends) worked the surface of this deposit and looked down into some of the old tunnels. Working from ground level up, Bill's group excavated a section of the exposed purple fluorite vein containing wulfenite. The tailings pile of purple fluorite at the north end of our shaft was made by Bill Hunt's group. Art Roe (1980) indicated six localities where acicular wulfenite (needles) can be found and stated that Bill Hunt (and others) found acicular wulfenite at the Great Southern mine in Yavapai County. That reference is actually to the Purple Passion mine, since Bill thought our mine site was part of the Great Southern mine and he labeled specimens accordingly (the Great Southern mine lies in a parallel vein about 1,500 feet to the east). Some time later, Bill's group found references which indicated the site is associated with a group of claims under the names of Kelly and or Hogan). The small amount of material that can be found in collections up until this time may be labeled under several alternative names such as the Kelly, the Hogan, or the Great Southern. Because of these labeling discrepancies, material that has the appearance of what is currently being mined, is almost certain to have come from the Purple Passion mine. If you have any of this previous material, please consider relabeling the specimens as being from the Purple Passion mine.
A stroke of luck and several days researching the file data at the Arizona Department of Mines and Mineral Resources (ADMMR) solved the mystery of the history. The Purple Passion mine is located at the site of what was known as the Diamond Joe mine. Due to an incorrect "guess" during a mapping survey, the ADMMR records had placed the Diamond Joe mine at one of it's prospect claims some distance to the east, and it was recorded as being in the southwest quarter of section 29 instead of it's true location in the southeast quarter of section 30.
The ore vein was discovered by a Mr. A.B. Lovell around 1890 and the ore was mined intermittently from 1901 until 1926. No assay records can be found for the early time period when the inclined shaft and vertical shaft number 1 were started. In 1926-27 a millsite was erected and a medium sized operation was started by the Diamond Joe Mining Company Inc. (the entire stock of the corporation was owned by a Mr. George R. Kyok of Wickenburg). The inclined shaft reached a developed length of 325 feet along the vein, for a depth of 225 feet. Vertical shaft number 1 intersected the inclined shaft at a depth of 83 feet and continued down to 180 feet. At that time, 60 tons of ore / week were being processed, averaging 12-15 % lead, 13.5 oz. of silver / ton and about .025 oz of gold / ton (no records have been found for molybdenum). Unfortunately at only 15 gpm, the mine did not produce enough water for processing the ore full-time when the production was increased to 100 tons / day. In an effort to keep the mill running, a 500 foot vertical shaft (number 2) was sunk in 1927-28. The first 225 feet were used as the main entrance to the lowest working level of the mine and the bottom 275 feet were used as a water reservoir. Roughly 135,000 tons of ore were removed and a total of 2,250 feet of tunnels, shafts, and stopes were driven, with levels at 45, 83, 180 and 225 feet. The reason there are no large tailings piles is that the vein was wide enough to make the tunnels with very little waste rock, so the tailings piles are mostly the barren material from the vertical shafts. All the ore was milled on site and processed prior to shipping. Late in 1928 the mine was closed due to insufficient water (Ghoering, 1934). ADMMR records indicate that the mine was briefly reopened in 1945, but only shipped a small amount of ore before reclosing.
GEOLOGY
According to the Arizona Bureau of Geology and Mineral Technology:
the "area is composed of a metamorphic-plutonic basement unconformably overlain by Tertiary volcanic and sedimentary rocks. The oldest rocks, assigned to the Proterozic (1.8-1.7 b.y.) Yavapai Supergroup, consist of amphibolite, schist, and gneiss, intruded by granite, leucogranite, and pegmatite. ...Proterozoic rocks are intruded by Late Cretaceous granodiorite, granite, pegmatite, and aplite. Basement rocks are cut by numerous felsic and mafic dikes and sills related to Tertiary volcanism. ...Volcanism was accompanied and followed by low- to moderate-angle normal faulting produced by northeast-southwest-oriented regional crustal extension. Major north-to northwest-trending moderate-angle faults, which dip 30 to 50 degrees to the southwest, cut and tilt Tertiary rocks and crystalline basement rocks, producing domino-style repetition of section.
...Precious-and base-metal prospects occur in both the Tertiary volcanic and sedimentary rocks and the crystalline basement. Many of the prospects are localized along low-to moderate-angle faults characterized by intense brecciation and quartz, calcite, and iron-oxide veining. Such mineralization is middle Tertiary in age."
According to Pratt (1938), the Purple Passion claim is located on the southerly slope of a batholith which has been eroded so that no sedimentary rocks are present. The uplift of the batholith has produced numerous fissures as channels for ore deposition. The main fissure strikes north 27° west dipping at 55° to the southwest. It is a true fissure vein, widened by displacement of the wall rock, and can be traced on the surface for a distance of about 3000 feet. The vein is cross faulted several times, but little displacement of the vein can be seen. The texture of the country rock is granitoid. It contains quartz, soda-lime feldspar, orthoclase, hornblende and biotite. Quartz predominates over orthoclase, and this makes the country rock a quartz diorite, shading to granodiorite. The mineralized vein has a banded structure, but in general one finds lead and silver minerals disseminated across the vein. Coarse-grained calcite predominates along the footwall, often intermingled with veins of quartz and purple or green fluorite.
Two distinct periods of mineralization are recognizable with the second period having a higher percentage of iron and silver. As the headwall is approached, an iron stained, leached calcareous material becomes prevalent, with a thin vein of galena between the two portions of the vein. The highly intruded condition of the hanging wall has resulted in extensive kaolinization which has widened the mineralized vein to a total thickness of 10 feet in some places. In arid districts such as this, the oxidized zone is liable to be extensive because the permanent water level is very deep. Furthermore, the Purple Passion mine lies at an elevation considerably above the nearest major water courses. However, since 1947 the surface water has flooded the old tunnels to about the 45 foot level. The old mining reports show that down to the 225 foot level the lead and silver minerals are mostly in their oxidized forms (the lead exists as anglesite and cerussite with a small percentage of galena; the silver is almost all chlorargyrite, with small amounts of silver sulfide or native silver present (Pratt, 1938).
MINERAL OCCURRENCES
| Anglesite - PbSO4 | Anglesite is typically found as a massive silvery-black submetallic ore in small seams and pockets throughout the vein. Sometimes the anglesite has a core of galena, and other times it serves as a core for further oxidation products such as cerussite or wulfenite. |
| Aragonite - CaCO3 | Aragonite occurs as a druse on other minerals in some pockets. |
| Barite - BaSO4 | According to Sedgwick (1923) in lead and silver veins of this kind, barium and zinc are usually well associated with the ore. In this respect, the mineralogy of the Purple Passion mine is a little atypical because only small amounts of barite and zinc are found. The barite occurs as translucent to white blades associated with the purple fluorite and sometimes with the calcite. The blades range in size from microscopic to as large as 3/4 of an inch. The striking contrast of snow-white barite blades and yellow wulfenite on purple fluorite produces some excellent specimens. Some micromount specimens have barite blades covered with purple fluorite crystals. |
| Calcite - CaCO3 | A fairly translucent white to yellow calcite serves as a major matrix material in the mine. Near the footwall, coarse-grained calcite dominates the vein with thickness up to 7 feet. Typically, pockets between these large calcite crystals contain quartz (clear, milky, smoky, and amethyst) or wulfenite crystals. In the pockets, the smaller calcite crystals are usually transparent and are intermixed with all of the other minerals. The calcite tends to fluoresce with the major colors being bright red or hot pink (the caliche coating also fluoresces a peach color). |
| Cerussite - PbCO3 | Cerussite is found as transparent colorless to honey or sherry colored adamantine crystals usually 1/4" or less, (although we have seen a 1" crystal from years ago). |
| Chlorargyrite - AgCl | As far down as 225 feet, chlorargyrite appears to account for the majority of the silver in the deposit. It occurs as a greenish or brownish to copper colored crust. Sometimes the chlorargyrite completely fills pockets in the fluorite matrix. |
| Fluorite - CaF2 | Fluorite occurs both as a purple or green granular matrix, and as seams or well defined crystals in pockets. The purple matrix is often botryoidal shaped and banded with deep purple and lilac colored layers. In some parts of the vein, the fluorite tends to be a translucent, vivid apple-green color, and occasionally traces of yellow or cranberry are present in the purple fluorite. Only a few pieces have been found with intergrown fluorite crystals up to 1/4 of an inch, but on the microscopic level (at 15x) the crystals are well defined cubes, octahedrons, and dodecahedrons. The green fluorite usually fluoresces a brilliant blue-white color. |
| Galena - PbS | Minor amounts of galena are found across the vein as thin stringers or small pockets, and it also occurs as a thin layer between the upper and lower portions of the vein. The galena is usually very fine grained (slightly blue in color) and the assays indicate it contains about 10% silver sulfide. To date, we have only seen one specimen with a small galena cube. |
| Gold - Au | The assays indicate .02-3 oz of gold / ton evenly distributed throughout the vein. Extremely small particles of free gold can be seen in some of the material. |
| Quartz - SiO2 | Quartz occurs as small seams and also as well formed crystals in pockets. Small clear quartz crystals are common, and pockets of amethyst, as well as lustrous smoky quartz are found occasionally. Small sceptered or reverse sceptered crystals are occasionally found at 15x magnification and phantom or banded crystals of all sizes are fairly common. The largest quartz crystals found so far are about 1/2 inch long and it should be noted that wulfenite crystals have been found on all of the varieties of quartz. Before splitting it open, the largest smoky quartz pocket measured about 10 x 7 x 2 inches and it contains crystals up to 1/4 inch long. |
| Silver - Ag | In addition to the chlorargyrite, silver is found as small wires, ribbons and globules in it's native form and as silver sulfide in the galena. The old reports indicate that silver sulfide was starting to be found as a separate mineral at the 225 foot level (Pratt, 1938). |
| Smithsonite - ZnCO3 | In this deposit, only small amounts of zinc are encountered (Sedgewick 1923); the zinc being found as smithsonite and as willemite. The smithsonite is found as white to greenish or aqua-colored microscopic botryoidal shapes. |
| Sulfur - S | Microscopic sulfur crystals are found - usually associated with the smoky quartz. |
| Uranium - U | Several specimens of wulfenite or purple fluorite have been found that are slightly radioactive (up to 50,000 disintegration's per minute) and the radioactive material was identified by gamma spectroscopy as uranium 238 and it's daughter products. The specific uranium minerals have not yet been positively identified although samples have been sent to be tested. |
| Willemite - Zn2SiO4 | The willemite occurs as microscopic sprays of transparent colorless to white or pinkish hexagonal crystals, often on a smoky quartz crystal matrix. The willemite strongly fluoresces a pale yellow color with spots shading to green (it is also phosphorescent). |
| Wulfenite - PbMoO4 | Wulfenite is distributed throughout the vein and also in fissures in the bordering country rock. The wulfenite crystals exhibit an array of colors ranging from dull opaque caramel and butterscotch through opaque yellow and orange to lustrous, transparent orange and yellow. The opaque color appears to be caused by surface weathering because the inside of the crystal remains transparent even though the crystal surface has turned an opaque yellow or butterscotch. Some of the wulfenite fluoresces a dull orange color. The crystal habits are: tabular, bipyramidal, pyramidal, acicular and acicular-tabular ("fuzzy tabs"). Commonly in cracks weathered out of the calcite, wulfenite specimens can be found as unattached clusters of intertwined blades, (usually quite battered) weighing from a few grams up to 3 kg. Unattached, opaque, tabular blades up to 2 inches on a side and 1/8 inch thick have been found. Attached blades up to 1 inch on an edge, have been collected on quartz, calcite and granular purple fluorite matrix. Occasionally, in pockets that were protected from the ground water, lustrous, transparent blades, up to 3/4 inch on an edge have been found. A small number of specimens exhibit zoning with concentric squares alternating between colorless and transparent yellow. |
The most interesting and complex habit of wulfenite found at the mine is the acicular-tabular crystals; we have coined the term "fuzzy tabs" to describe them. They have the appearance of two scrub brushes placed back to back. These have been determined to be a true epitaxal growth with the c axis of the wulfenite needles aligned with the c axis of the original wulfenite crystal. The fuzzy tabs have a normal tabular crystal in the center which sprouted a secondary growth of needles perpendicular to the side of the wulfenite tab. The needles usually grew an equal distance out of both sides and the original crystal shows as a dark band down the center of the fuzzy tab. In pockets containing fuzzy tabs, the mineralizing solution often grew small needles lining the rest of the pocket.
Nearly 50% of the wulfenite specimens found at the mine have acicular crystals which are very elongated pyramids and bipyramids (only a small percentage of the wulfenite formed the more normal short bipyramids). These needle shaped crystals tend to be a drab, opaque tan to a translucent, honey-yellow color. The largest wulfenite pyramid was about 5/8 of an inch long and 1/16 inch in cross section (unfortunately, it broke while trimming the specimen). The wulfenite needles sometimes bundle together like a stack of logs to form multiple crystals which do not appear to have a tabular crystal in the center. These bundles of needles look different than the fuzzy tabs, because they do not have a center stripe and the proportions are not the same.
CONCLUSION
To date over 14 minerals have been found with many of the minerals being well crystallized and abundant. Some of the minerals display multiple crystal habits and there is a substantial number of mineral associations that may be found on a single specimen. Considering also the vivid color combinations (and with some of the minerals being fluorescent), an extensive range of attractive specimen material is available. The majority of the specimens that are currently being produced are micromount or thumbnail sized up to small cabinet pieces, with an occasional larger specimen. The current shaft is about 25 feet below grade and the mine is producing larger and gemmier specimens with depth. We expect that the Purple Passion mine will eventually connect to the Diamond Joe tunnel system.
ACKNOWLEDGMENTS
Darrel Dodd put us in contact with many interested parties including Bill Hunt and Steve Decker. Bill Hunt performed chemical tests to identify minerals, took stereoscopic photomicrographs and also provided a wealth of information about the site. Steve Decker wrote a short article about the mine and placed it on the Internet. Niles Neismith guided us through the maze of data at the Arizona Department of Mines and Mineral Resources. The photographs and photomicrographs were taken by Bill Gardner, Bill Hunt and Gary Spraggins. Collecting on the claim is permitted on a fee dig basis. For more information please contact Bill Gardner at (602) 547-2234 or Ed Davis at (602) 569-2474.
REFERENCES
Mineralogy of Arizona 3rd Edition, Anthony, John W.; Williams, Sidney A.; Bideaux, Richard A.; and Grant, Raymond W. (1995) University of Arizona Press. pg. 426.
Arizona Bureau of Geology and Mineral Technology, Open-file Report 87-9, Geologic Map of the Wickenburg, southern Buckhorn, and northwestern Hieroglyphic Mountains, central Arizona, Stimac, James A.; Fryxell, Joan E.; Reynolds, Stephen J.; Richard, Stephen M.; Grubensky, Michael J.; and Scott; Elizabeth A. (October, 1987)
Roe, A. (1980) Micromounting in Arizona, Mineralogical Record, 11, 264.
Sedgwick, A.E. (1921 and 1923), Report on the Diamond Joe Group of Claims, Arizona Department of Mines and Mineral Resources, Primary Data File - Diamond Joe 3/20/90.
Gohring, W.B. (1934), Report on the Diamond Joe Mining property, Arizona Department of Mines and Mineral Resources, Primary Data File - Diamond Joe 3/20/90.
Pratt, M.E. (1938), Report on the Diamond Joe Mining property, Arizona Department of Mines and Mineral Resources, Primary Data File - Diamond Joe 3/20/90.
*Note: Ed Davis sold his interest in Purple Passion to Dick and Bess Shields in the Summer of 2006. Visitors to the mine should contact Bill Gardner or Dick and Bess Shields for permission.