Order L-208, A Gold Mine Waiting to be Mined Again

Ever hear anything about the War Minerals Board Order L-208? If you haven't, and you are a gold prospector, it is something you will want to learn about, because it can lead you to a good, abandoned gold mine!

It turns out that during world war II, the US government ordered all non-essential mines (i.e., gold mines) to close and focus all efforts on the war. After the war, many of these commercial gold mines that were producing gold at a price of $35.50 per ounce when closed during the war, never reopened because many did not come back from the war, lots of the closed mines and mills fell into disrepair, many flooded, and after the war, our country focused on infrastructure, rather than gold. 

So, imagine you found one of these old mines in Arizona. Today's gold price (2/23/2022), according to the blogspot "Searching for Gold" is $1,908 per ounce, or nearly 54 times higher than it was when during World War II. So, nearly every L-208 mine likely is commercial at todays price! 

These and other mines are described, in a new book available on Amazon entitled, "Gold in Arizona". And there are many other gold anomalies described in the book, including those associated with detachment faults. So, the book provides information on dozens of detachment faults and prospects in these unusual types of faults that run from the northwestern part of the state to the southeastern part of the state.

Kindle version on Amazon

It took a few years, but finally, Gold in Arizona - A Prospectors Guide was published in December, 2019. After researching gold deposits in Arizona, it is clear to me that Arizona is not only the copper state, but would better be known as the Copper-Silver-Gold state. 

Hard to believe, but Arizona has produced much more than 500,000,000 ounces of silver and 16,000,000 ounces of gold along with all of its copper, zinc, lead and turquoise. So, in this book, many of the old mining districts are described with many of the mines. And, there are many deposits that have been overlooked, and many that have only been partially prospected.

Ezra 8:27

United Verde Mines, Jerome (Verde) district, Arizona

Black Smoker from the bottom of the ocean
in Arizona! Yes, when this hydrothermal vent
was active more than 1.7 billion years ago, 
Arizona sat at the bottom of an ancient ocean
where deep hot-springs emitted gas and sulfides
from such vents and produced one of the greatest
massive sulfide deposits ever found, and high
and dry, Jerome, Arizona.

From Flagstaff, we decided to take a detour to the Verde district: a highly mineralized area. The district is 90 miles north of Phoenix along the edge of the Black Hills in Yavapai County, central Arizona and locally referred to as the Jerome district. It encloses a 30 mi2 mineralized terrain with two major mines along the northern edge of the town of Jerome. The two principal mines in the district are the United Verde and United Verde Extension. To get to the district, drive south on Highway 89A from Flagstaff. You can also visit the town on your computer by searching for “Jerome, AZ” with Google Earth.

On the northwestern edge of Jerome is a large, partially reclaimed, open pit mine that is part of the United Verde mine. The rest of the mine lies underground and inclues 81 miles of tunnels and shafts hidden beneath the open pit, Cleopatra Hill and the adjacent valley. A large active quarry is visible near the northeastern edge of town that is actually the Clarkdale quarry and cement plant, which has little to do with the base metal mines. Evidence of the old smelter works is visible further east near the Verde River and expressed as black slag with some old buildings and foundations.

If you are familiar with gossans, you should be able to trace an extensive belt of rusty-colored rocks on aerial photographs on Google Earth. I followed the gossan 7 miles north of the United Verde Mine, and another 7 miles south! Such an extensive gossan likely hides ‘blind deposits’! My experience is that for every mineral deposit found on the surface, there likely is many more hidden at depth in the immediate area (and who knows how many lie hidden under the adjacent valley sediments). And like most mines reported to have been mined out, the United Verde is far from being mined out. In fact, the US Geological Survey reported at least twice as much unmined ore remains in place as was mined in the past. Actually, it is extremely rare for a major mineral deposit to be mined out as most productive mines terminate operations because of declining economics as prices and markets fall during bad times.

Jerome, Arizona, looking towards Cleopatra Hill. The hill with the ‘J’ is Cleopatra Hill and the 

United Verde open pit is the mine dump seen in distance to the right of the J between the two 

prominent hills. The tops of two head frames of the United Verde Extension mine are visible in the

foreground.

When I was a student in geology, the Verde district was considered as an exploration model for ‘submarine volcanogenic massive sulfide deposits’. One geological dictionary defines massive sulfide very simply as: “an unusually large deposit of sulfide minerals”. But there is more to massive sulfide deposits.

Massive sulfides bring thoughts of copper and zinc to geologists. And for myself, I also think of precious metals. Sulfide minerals in many of these can enclose significant amounts of gold and silver. So much silver was found associated with these deposits at Jerome that the recovered silver essentially paid for the mining operations. And many banded cherts (known as exhalites) associated with ‘submarine volcanogenic massive sulfides’ (VMS) contain anomalous gold.

VMS refers to a type of mineralization with zones of massive (as well as disseminated) sulfide minerals that were deposited beneath the ocean in hydrothermal vents including white and black smokers. Over geological time, many of these VMS deposits now lie on dry land due to tectonic forces while modern deposits continue to form under the ocean. Where found, VMS deposits are hosted in rocks 3.55 billion years old to the present and may even include deposits with a hundred million tons of ore rich in gold, silver, copper, zinc, lead and other metals.

White smoker sinter column. White smokers precipitate in hydrothermal vents and often 

have auriferous silica. Black smokers are sulfide rich and associated with higher 

geothermal temperatures (specimen from the United Verde mine, and on display at the 

Douglas Museum in Jerome).

VMS deposits have distinct rocks such as volcaniclastics (breccias) that represent very active submarine vents. Some of these are so distinct that one Canadian geologist dubbed them ‘mill rock’ years ago because he noticed there were operating mills and mines adjacent to many of these.

In addition to volcaniclastics (mill rock), siliceous mounds or chimneys are formed by submarine fumaroles that are referred to as black and white smokers. Other distinct rocks include layered stratiform rock known as exhalites that formed during eruption of heterogeneous volcanic material in sea water: the layering was produced by sea water naturally separating minerals by specific gravity as they slowly settled in the ocean water.

The host rocks for the VMS deposits in Jerome are 1.7 billion years old and similar in age to VMS deposits discovered in Colorado and Wyoming in 1979 and the early 1980s. You might be wondering what submarine VMS deposits are doing in the dry deserts of Arizona and high mountains of Colorado and Wyoming? In the geological past, these were accreted to continents and buried by tectonic forces related to continental drift. After millions of years of erosion following mountain uplift, some have been exposed at the surface, while many more remain hidden and undiscovered. Those hidden at depth are referred to as ‘blind’ deposits. Still others continue to form in the oceans, particularly along active volcanic island chains (such as Japan) and along spreading centers such as the Mid-Atlantic Ridge.

When I was the Senior Economic Geologist and Deputy Director at the Wyoming Geological Survey, Conoco Minerals discovered VMS deposits in 1979 in the Sierra Madre Mountains west of Saratoga. But few have heard of these deposits because of the US Forest Service. Those that were found near the old Itmay mine, not far from the famous Ferris-Haggarty mine, were withdrawn from public use. Other VMS deposits were soon found in Colorado and Wyoming. The discoveries sent shock waves through the Forest Service which had little taste for mining; and the agency hurried to withdraw the new discoveries until all, or portions or most VMS deposits fell within or adjacent to the withdrawals effectively locking out mining companies and prospectors from public land.

Much of this region in Colorado and Wyoming was known as the Grand Encampment district, which in the 19th century, prior to government interference, was a major base metal district. But because of the withdrawals, no jobs were created because of Conoco’s discoveries, no valuable metals were mined, and the US continued out-sourcing jobs and importing base metals.

Today, the Verde district is idle and the town of Jerome is a tourist attraction built on the flank of Cleopatra Hill which rises more than 6,000 feet above sea level. Some buildings in Jerome were constructed on the Precambrian rock that forms Cleopatra Hill, while the rest of the town slopes downward on Tertiary to Recent fanglomerates and landslide debris. The landslide has been a historical problem and periodically slides following periods of high runoff. At the base of the slope, the surface flattens eastward to the Verde River valley at Clarkdale and Cottonwood 4 to 5 miles east of Jerome at an elevation of 3,300 feet.

Production

Jerome was a major copper-gold-silver-zinc-lead district. According to the Arizona Department of Mines and Mineral Resources (2007), 48 of 70 known VMS deposits found in Arizona have produced ore - all of which are Precambrian age (1.7 to 1.8 billion years old). Production from these totaled more than 55 million tons. Most of these deposits are steeply plunging and deformed, such as the United Verde, which has been described as a rod-like ore body or pipe located within an axis of a major, steeply-plunging, fold.

About 98% of the past production in the Verde district was from the United Verde and United Verde Extension mines. Even though mining ceased in 1953, there is evidence that the miners left behind considerable ore. The district was considered to be a copper district, but at today’s metal prices, the district would be classified as a copper-gold-silver-zinc district. Considerable copper, gold, silver with some zinc and small amounts of lead were recovered from the two principal mines.

In 1989, the US Geological Survey indicated records from Phelps Dodge showed production from the United Verde Mine from 1884 to 1975 amounted to more than 2,926,900,000 pounds ($10.1 billion at 2012 prices) of copper, 97,891,000 pounds ($82 million) of zinc, 459,000 pounds ($390 thousand) of lead, 49,603,000 troy ounces ($1.4 billion) of silver, and 1,354,200 troy ounces of gold. Koschmann and Bergendahl of the US Geological Survey reported gold production was even higher at 1,571,000 ounces ($2.5 billion) over the lifetime of the district. Based on statistics from the U.S. Geological Survey and Phelps Dodge, the United Verde produced $14.8 billion in metals at 2012 prices.

High wall of the United Verde open pit mine with head frames in foreground. Note large distinct, rusty gossan produced by oxidation of massive sulfides in the background. The massive sulfides were so rich that they actually ignited and burned underground for many years!

History

The cupriferous gossan exposed at the surface at Jerome was found by prehistoric tribes hundreds of years ago. In 1875, the U.S. Army rediscovered the gossan and in the following year (1876) prospectors rushed to the district to claim the discovery. By 1882, much of the minable land had been consolidated by the newly formed United Verde Copper Company which began extracting near-surface oxidized and supergene enriched copper ore rich in gold and silver. Underground mining began in 1883, and open pit mining was initiated in 1920.

A second company, (United Verde Extension [UVX]), was organized in 1899 to search for a suggested, down-faulted continuation of the United Verde massive sulfide. UVX began searching southwest and east of the United Verde property. Their efforts were fruitless until they were on the verge of bankruptcy in 1914, when a drift driven from a shaft east of the United Verde mine intersected bonanza grade ore rich in chalcocite on the 1,200 level. In 1916, another ‘blind’ deposit was found. The ore was so rich the company ended the year with a 74% profit after expenses. Later geological studies showed the UVX discoveries were not part of an off-set of the United Verde ore body, but instead completely separate, ‘blind’ ore bodies.

The UVX mine operated on a large scale until 1938 when much of its high-grade was mined out and operations ceased. The nearby United Verde mine continued mining. After 1931, much of their activity focused on open-pit mining. Depletion of ‘high-grade’ reserves finally forced the mine to close in 1953. This resulted in many people reporting that the deposit was mined out. However, the operations left behind a giant, low-grade, ore deposit and who knows how many ‘blind’ deposits.

Geology

The VMS erupted as hot, sulfide-rich material into cool water resulting in precipitation on the ocean floor 1.7 billion years ago. The Verde VMS lies at the top of a submarine rhyolite dome and flow breccia known as the Cleopatra Member of the Deception Rhyolite. The ore is zoned and capped by chert and siliceous massive sulfide that grades down into pyrite-rich massive sulfide, zinc-rich massive sulfide, copper-zinc-rich massive sulfide, chloritic stringer ore, and chloritized quartz porphyry ore. Gold is found throughout but is in greater concentrations at the stratigraphic top (siliceous massive sulfide and chert ore).

Gold is in greater concentrations in chert. For instance, on the 4500-foot level, the black schist yielded 0.002 opt Au and 0.71 opt Ag. In chert near the surface, the ore yielded values as high as 0.12 opt Au and 4 opt Ag (60 times more gold). On the 700-foot level, the massive sulfide averaged 10 times more gold than the black schist. A positive correlation of gold with higher zinc content was also recognized by the US Geological Survey. This is important as much zinc ore was not mined.

Sulfides are exposed at the surface down to the 4500-foot mine level, but in the geological past, the ore also extended upwards to the base of the Cambrian Tapeats Sandstone indicating at least 350 feet of vertical column of massive sulfide was removed by erosion. With this much erosion, drainages down-slope from the massive sulfide should contain detrital gold, but I could not find any report suggesting that gold had been detected in the nearby drainages. Based on the mode of occurrence, the gold would likely be very fine grained.

Ore minerals in the massive sulfide in decreasing abundance included pyrite, sphalerite, chalcopyrite, bornite, arsenopyrite, galena, tennanite and gold (electrum). Much of the electrum is thought to be present as microscopic inclusions in sulfide minerals. Silver is present in the electrum and in late-stage tennanite (Cu12As4S13) in quartz carbonate veins and in carbonate rich massive sulfide ore. The tennanite also contains gold as microscopic inclusions.

The Verde was the largest known volcanogenic massive sulfide deposit in the US with 33 million tons of mined ore, and 50 to 70 million tons of low-grade ore left in place. It is also considered to be one of the largest in North America. The massive sulfide was steeply-dipping, irregular- to cylindrical-shaped ore body approximately 700 to 800 feet in diameter that extended 2,400 feet deep. The United Verde mine reached a depth of 3,515 feet and included eight shafts. According to the US Geological Survey, proximal ore recovered from the mine averaged 4.77% Cu, 0.046 opt Au, and 1.65 opt Ag. Zinc and lead were not recovered during much of the operations. Another blind ore body was found in the lower levels of the mine 500 feet northwest of the roots of the main deposit.

Anomalous gold was detected in the pyritic and sphalertic massive sulfides and the chert rich ore: chloritic host rocks are poor in gold. The zinc ore contained as much gold as the copper ore. And because only the high-grade copper-rich portion of the massive sulfide lens was mined, a very large tonnage of low-grade ore remains in place and it was estimated that at least 75% of the mineralized deposit remains unmined because it was too low-grade to mine (<2% Cu) under historical economics. The estimates suggest about 115,000,000 tons of low-grade massive sulfide ore and 38,000,000 tons of mineralized black schist remain in the mine with grades of 0.5 to 1% Cu, 2 to 4% Zn, 0.01 to 0.015 opt Au and 0.5 to 1.0 opt Ag. This zinc-rich deposit is estimated to have 400,000 troy ounces of gold.

At the United Verde Extension Mine, mineralization occurred in an elliptical ore body hosted by the Deception Rhyolite and Grapevine Gulch Formation. The main chalcocite ore body was found on the 1400-level and was 269 feet wide and 440 feet long on this level.

You may not appreciate this exhibit at the Audrey Head-frame Park in Jerome if you have.

a fear of heights. Sunlight is projected down the 1900-foot deep Audrey shaft so visitors can

see the depth of these mines. When I took this photo, I was standing on the plexiglass

covering the deep shaft.

The UVX mine produced 3,879,000 tons of ore that averaged 10.23% Cu, 0.039 opt Au, and 1.71 opt Ag. Ore minerals included chalcocite, cuprite, native copper, malachite, chrysocolla and azurite hosted by felsic fragmental rocks, massive rhyolite and quartz porphyry – all units of the Deception Rhyolite.

Part of the UVX operation was developed by the Haynes Shaft due west the United Verde open pit. This deposit was another blind ore body found at 2,500 feet below the surface. The UVX decided to explore the ground under the Haynes shaft by driving a tunnel at the 3,000 level. A drift was started in 1930 and reached the Haynes massive sulfide pipe in 1931.

The Haynes proximal pipe was a steeply-plunging massive sulfide. It extended a short distance above the 2700-level downward to an undetermined point between the 3450 and 3700 levels of the United Verde Mine. The Haynes haft was sunk to 700 feet between 1907 and 1911; subsequently deepened to 1,200 feet, with 1,700 feet of drifts and crosscuts on the 700 level and 700 feet on the 1200 level.

Gold Basin District, Arizona

Many dry gold placers are found along the eastern edge of the White Hills extending east to Hualapai Wash in Mohave County (T28 & 29N, R17 & 18W), NW Arizona. These are the Gold Basin placers. Search for "Gold Basin, AZ" on Google Earth, and hopefully, you will arrive in the middle of Gold Basin, a short distance east and south of the many dry gold placers known in this basin. 

The area lies south of Lake Mead, the Lake Mead Recreation area, and the Colorado River. The nearest communities are Meadview (36o00’00”N; 114o04’00”) and Dolan Springs (35o35’25”N; 114o16’25”W). Due to the large number of retirees and snowbirds in the region, each community is surrounded by suburbs.

The placers are dry placers in the desert, and these contain detrital gravels (1 to 5 feet thick) that mostly lie on hard, false, bedrock of consolidated gravel cemented by caliche - unfortunately, there is no shortage of caliche in Arizona. The overlying gold-bearing gravels are weakly mineralized with considerable black sand, quartz, and rock fragments of schist and gneiss eroded from the Precambrian terrain in the White Hills. 

Gold content of the placers is poor and may only be 0.03 to 0.04 ounce per cubic yard at best; while the underlying consolidated gravel remains mostly unexplored. Gold nuggets are rare. Some up to an ounce have been found with the largest only 4 to 5 ounces in weight. Much of the gold-bearing area is part of the White Mountains alluvial fan that extends from the eastern flank of the uplifted White Hills to Haulapai Wash to the east. The fan covers a surface area of 6 by 5 miles and you can drive to the area northward on the Pierce-Ferry highway (Road 25) through Dolan Springs. 

Lode gold was discovered in quartz veins in Precambrian rock in the 1870s. Placer gold from the veins was not found until the Great Depression. In 1932, W. E. Dunlop found gold in the dry gravel which attracted others. The amount of gold recovered by the prospectors was minor. Even experienced miners only made about $1 per day (1933 wages). And the total amount of reported gold recovered from the Gold Basin placers is only 415 ounces produced during the period of 1934-49. 

The gold-bearing gravels occur in arroyos and gulches at elevations of 3,300 to 2,900 feet. The gravels have medium-grained, angular schist and gneiss fragments with a minor amount of finely divided quartz. A small number of boulders are encountered that are generally less than 2 feet in diameter. The gold occurs as flour gold and less commonly as angular nuggets with some gold attached to black schist particles. The White Hills, which are made up of granitic, schistose, and volcanic rocks, contain many argentiferous and auriferous quartz veins that are the likely source for much of the Gold Basin gold (Wilson, 1981).

The gold placers have erratically distributed gold. In addition to dry placer mining, there is considerable prospecting with metal detectors. Some find gold, while others have found a bonus of meteorite fragments.

Moss Gold mine, San Francisco District, Oatman, Arizona

“With thy wisdom and with thine understanding 

thou hast gotten thee riches, and hast gotten

 gold and silver into thy treasures:” Ezekiel 28:4

Arizona is known for many, giant copper porphyry deposits. The state's endowment of base metals, sometimes results in other deposits being overlooked by mining company execs even though the state has dozens of very attractive gold, silver, and massive sulfide and replacement deposits. The copper porphyries occur in extensive volcanic fields, filled with volcanic and plutonic rocks associated with large envelopes of hydrothermal and metasomatic alteration and mineralization. Overall, such geological environments are favorable for porphyry copper, gold, silver, lead, zinc, molybdenum deposits, associated copper, lead, zinc, manganese massive sulfides, replacement copper, silver deposits, gold, silver, copper vein deposits, and some gemstones and lapidary material (i.e., fire agate, opal, chalcedony, quartz crystals, chysocolla, turquoise, wulfenite, geodes, etc). Overall, the copper state has many very attractive gold deposits described in various geological reports and thesis studies at the US Geological Survey, Arizona Geological Survey, Arizona Geological Society, and publications and geological thesis projects at various universities in the state.

Reports by the Arizona Geological Survey and USGS, and papers by Hausel (2010, 2011a, 2011b, 2013) and books (Hausel, 2019, 2020) provide summaries of the many gold deposits in Arizona. One of these gold deposits, known as the Moss, was reopened in 2018. The historical mine not only has significant gold mineralization left in-situ by early miners, but also appears to have very good potential for discovery of additional gold resources in the nearby area extending both east and west of the historical workings.

Moss and Mossback mines, San Francisco (Oatman) district, Arizona showing locations of 
anomalies (yellow pins) and lineaments (red lines). Google Earth

The Moss lies 2-miles, on-trend, west of the Mossback mine (inactive), 5.5 miles northwest of the Gold Road mine (active), 11 miles southeast of the Katherine gold mine in the Union Pass district, and is the northernmost extent of known gold mineralization in the San Francisco district of the Black Mountains. Nearby towns include Bullhead City (6-miles west), and Oatman (6-miles southeast). 

The Moss mine is located on the Moss vein: the vein, which has an N60oW-trend and 60o to 70oSW-dip. The mineralized structure is 45-feet wide locally, and pinches and swells along strike (Wilson and others, 1981). Gardner (1936) reports the structure to range from 20- to 100-feet wide: with mineralization in extensive stockworks and silicified zones. The deposit is described as epithermal, low-sulfide, quartz-calcite vein and stockworks system extending over a strike length of at least 4,500 feet (Nolan, 2010). Gardner (1936) indicates the vein could be traced for more than a mile along strike. 

The vein is hosted by Tertiary, Moss quartz monzonite porphyry (Gardner, 1936; Noland, 2010), with the structure being open along strike and at depth. In the past, shafts were sunk 100- and 230-feet deep with 1,700-feet of drifts. A calcite-quartz stockworks vein occupies the hanging wall of a high-angle fault and is overlain by as much as 100-feet of low-grade, mineralized, stockworks and siliceous breccia classified as low-sulfide, adularia-sericite, epithermal vein typical of many near surface, hydrothermal systems. Such deposits are often related to paleo-hot springs and/or shallow geothermal systems. The vein has some fluorite (Lausen, 1931). 

Along the southern portion of the vein, a group of conjugate veins occur in the hanging wall that have a similar trend, but dip northerly. Much of the historical gold and silver production from the vein was from conjugate veins. 

In the 1980s, Harrison Mining dewatered the shaft and mined 3,000 to 5,000 tons of ore that averaged 0.29 opt Au. In 2004, Patriot Gold Corporation optioned the property and identified auriferous veins unrelated to the primary vein that include the Discovery and Ruth veins. In 2009, Northern Vertex picked up the property and drilled more than 670 holes (Preston, 2013). 

Using a 0.01 opt cutoff grade, the Northern Miner reported the deposit has 22.6 million measured and indicated tonnes grading 0.023 opt Au and 0.26 opt Ag, plus 3.9 million inferred tonnes averaging 0.017 opt Au and 0.2 opt Ag. In total, known resources include 603,000 ounces of gold and 6.6 million ounces of silver within 650 feet of the surface (Preston, 2013, Wilson and Redwood, 2012). 

Holes drilled in the western extension of the vein were designed to test near surface quartz-carbonate stockworks open to the south. Multiple zones of stockworks veining (randomly oriented veins and veinlets, sometimes referred to as stinger zones) encountered within 500 feet of the surface, suggest potential for widespread mineralization to continue south. Eight additional drill holes demonstrate strong development of quartz-carbonate veins, breccia and stockworks that continue from the surface to at least 650 feet deep. 

An airborne magnetic survey by Patriot Gold indicates the Moss structure is a well-defined, magnetic high. The survey identified 1.8-miles of unexplored magnetic structure, and also identified nine linear structures associated with known mineralization, and one 3.6 mile structure was likely an extension of the Gold Road deposit. Recently, a heap leach pad was constructed south of the Moss vein (35°5'43"N; 114°26’55"W) presumably to extract gold from low-grade ore. Northern Vertex poured its first gold bar in early 2018. 

At the eastern extent of the mineralized zone, the Mossback mine lies along the edge of Mossback Wash. The property was claimed in 1863 and a shaft sunk to a depth of 800 feet. The vein is in andesite and as much as 90-feet wide with an 80o dip. Vein-filling consists of brecciated andesite and calcite with subordinate amounts of quartz, with spotty ore. In addition, the area appears to have an extensive gossan based on aerial photography (Hausel, 2020).

Recently, Elevation Gold Gold Mining Company published mineral resource estimates of gold and silver for the Moss mine as of December 2019. They report measured, indicated and inferred resources totaling 489,000 ounces of gold and 5, 838,000 ounces of silver. 

Elevation Gold optioned the Moss in 2011 and constructed a pilot plant in 2014. After construction and commissioning of the mill and mine in 2018, Elevation Gold announced commercial production at the mine, effective September 2018. 

The operation features a an open pit. The ore is crushed, agglomerated and heap leached followed by processing in a metal recovery plant and refinery, with a final process of production of gold and silver doré bars. 

An updated mineral resource estimate incorporating results of a 2019 reverse circulation infill drill program was disclosed in a December 18, 2019 press release. Drilling to the west of the current mining operation demonstrated there are significantly more resources within and adjacent to the open pit. 

"The resource estimate update found that from the start of operations to December 31, 2019, mining operations depleted approximately 71,000 ounces of gold, however with drilling success, these mined ounces have been more than offset by an addition of 86,000 ounces of gold in the inferred category. In comparing the updated December 31, 2019 resource estimate to the resource estimate in the Technical Report, aggregate measured and indicated gold ounces fell by approximately 8% primarily due to depletion from mining activities, while inferred gold ounces grew by almost 300% due to the identification of new resources from infill drilling. Exploration upside potential at Moss is excellent as the deposit continues to remain open for resource expansion along strike (at both ends) and at depth". 

TECHNICAL REPORT

Technical Report, 2021 on the Mineral Resource, Mineral Reserve, and Mine Plan for the Moss Mine

Goldfield Arizona - A Good Tourist Town.

The Goldfield district lies in the foothills of the Superstition Mountains at the extreme northeastern edge of the Phoenix valley, 5 miles northeast of Apache Junction and 40 miles east of Phoenix. The district extends from Pinal into Maricopa County along the margin of Arizona’s Transition zone within the Basin and Range province. 

Gold was discovered in 1892, and led to construction of Goldfield boomtown. The town was occupied by more than 1,500 residents with a post office established on October 7, 1893. The rush was short-lived. By 1897, many mines lost their glitter, and miners packed up and left Goldfield to the ghosts. 

But the ghosts were again haunted by miners and prospectors when a second community was established at the original townsite, and renamed Youngsberg. Mines re-opened, and a mill and cyanide plant built to recover gold, and a Post Office established on March 15, 1920, two years after the end of the first world war. 

But the mines again lost their attraction and the town was vacated in 1926, leaving it in the hands of ghosts. Today, the town has been revived by tourist trade and the town stands once again with both the living and the dead. The tourist attraction, a replica of the old mining town, provides exhibits of old mines, a brothel, saloon, museum, livery, gift shops, galleries, gold panning and more. You can even take a mine tour and sometimes see a gunfight. It is a highly recommended stop when visiting the Phoenix east valley, whether you are sentient or ghost.

Goldfield is accessed from Route-88 (North Apache Trail). Along the way, you will drive by the Superstition Mountains Museum. This is a highly recommended stop with old stamp mills, and information on the Lost Dutchman mine. After your museum tour, Goldfield is just another 0.8-mile up the road on the left. The Goldfield 7.5-minute quadrangle encloses much of the district and shows locations of some mines and prospects.

Wilson and others (1967) report that the district is covered by a pediment surface overlying coarse-grained granite, granite breccia, granite pegmatite and indurated (hardened) arkosic conglomerate. The principal mines in the district lie along north-trending, (west-dipping) shear zones (faults). 

The most productive mineralized zone at Goldfield was known as the ‘Mormon stope’ mostly mined out prior to 1898 at the Mammoth mine, north of the town. A stope was developed on an ore shoot, discovered north of the main Mammoth shaft at an intersection of a cross-fault with a shear zone, which provided permeability favorable for gold to flood the structure. The caved portion of the stope is 100-feet by 25-feet where granite is stained by limonite with irregular stringers of coarse-grained, white, quartz. Limonite (some gold-bearing) is likely derived from pyrite oxidation.

The district is best known for sporadic, fault-controlled, rich, ore shoots in large blocks of low-grade gold ore. During its heyday (1893 to 1898), the Mammoth, Bull Dog, and Black Queen mines produced about 60,000 ounces of gold and 20,000 ounces of silver. You can find out the value in present day's dollars by using links on Searching for Gold. 

There are no known reports of placer gold in the district other than a passing statement by Dinsmore (1911) stating that within a 3 by 8 mile area, “gold may be panned anywhere”. A sediment-filled arroyo crosses the mineralized structure to the north and west of Goldfield, and likely has some gold. Based on some of the reported high-grade zones in the faults, it is likely a few nuggets and gold dust lie buried in sand and banks of the arroyo (search Google Earth for ‘Goldfield, AZ’). Like most stream beds in the desert, it is rare to see standing water in this drainage except after rare downpours. Since the drainage receives runoff from the nearby Goldfield Mountains, flash floods are not uncommon. 

Gold was discovered in this area following a flash flood that exposed granite porphyry breccia containing visible gold. The granite was covered by arkosic conglomerate before it was exposed by the flood waters (arkose is a sedimentary rock with considerable quartz and feldspar and of similar composition as granite). Prospectors reported some very old mine workings were found in the area, indicating gold had been sought by unknown miners prior to 1892. 

The principal mines are the Black Queen, Bulldog, Mammoth and the Old Wasp; however, other mines and prospects were dug including the Bluebird, Doc Palmer, Copper Crown, Tom Thumb, Fairstake, Treasure Vault, Golden Hillside, Highflyer, Lazy Doc, Goldstake and Gold Bond. These are described by Hausel (2020).

ARIZONA Mines, Mills, Ghost Towns, Mining Museums & Tours

Arizona has a plethora of mines. If you would like to learn about these, visit museums, ghost towns and various rock hound and prospecting clubs. Before you begin your tour, get a couple of books and examine websites to assist you on your sojourn through the Arizona Outback.

Obtain a copy of Gold in Arizona -A Prospector's Guide. This book provides information on geology, mining history, ghost towns, mineralogy, and is the only book of its sort on Arizona that also provides GPS coordinates to mines in Arizona. So, you can search for these on Google Earth and plot access routes before you head for the hills. The 2019, 376-page book is available at Amazon. Or if you prefer, you can get a modified 2020 Kindle Edition. More information is available on my GemHunter website as well as on some of my blogspots. And be sure not to follow anyone on Facebook.

Ajo Historical Society Mine Museum in Ajo
Arcadia Ranch Museum in Oracle
Arizona Capitol Museum in Phoenix
Arizona Geological Survey, Tucson, Arizona
Arizona History Museum in Tucson
Arizona Museum of Natural History. in Mesa, Arizona
Arizona Public Lands - BLM
Arizona Science Center in Phoenix (sorry, we do not support those who require masks)   
Audrey Headframe Park in Jerome
Bagdad Mining in Bagdad.
Bagdad mine overlook in Bagdad  
Black Hills Rock Hounding near Safford
Bullion Plaza Cultural Center and Museum in Miami
Castle Domes Mines Museum in Yuma
Cave Creek Museum
Contention City Ghost Town near Tombstone
Copper Art Museum in Clarkdale
Desert Caballeros Western Museum in Wickenburg
Douglas Museum in Jerome
Fairbank Milling town near Tombstone
Fire Agates
Fire Agate Localities
Fire Agate Lapidary
Fire Agates at Deer Creek, Arizona
Fire Agates in Oatman Mining District, Arizona
Fire Agates RockHounding Area, Saddle Mountain, Arizona
Fire Agates at Slaughter Mountain, San Carlos Reservation, Arizona
Gemstones in Arizona, Gemland
Geology Tours, Gemland
Ghost Towns of Arizona
Gold King Mining Museum in Jerome
Gold Panning Area, Lynx Creek near Prescott
Goldfield Arizona Ghost Town near Apache Junction
Good Enough Mine Tour in Tombstone
Grand Canyon Tours
Greenlee Historical Museum in Clifton
Greenlee Rockhounding
Jerome Mine Museum
Kartchner Caverns in Benson
Millville Tour near Tombstone
Mineral Museum, University of Arizona, Tucson
Museum of Casa Grande
Old Dominion Mine Park in Globe Arizona
Planet Mine, Arizona and nearby ghost towns of the Swansea Mining district.
Queen Mine Tour in Bisbee
River of Time Museum in Fountain Hills
Rock Hounding Arizona
Rock Hounding on Public Land in Arizona
Rock Hounding Sites Gator Girl
Ruby Ghost Town south of Arivaca, Arizona
Superstition Mountain Lost Dutchman Museum in Apache Junction
Tombstone Arizona
Vulture Mine Tour near Wickenburg
World’s Smallest Museum in Superior

Rockhound and Prospecting Clubs
Apache Junction Rock Club
Arizona Association of Gold Prospectors (Phoenix)
Daisy Mountain Rock and Gem (phoenix)
Desert Gold Diggers (Tucson)
Gila County Gem & Mineral society (Miami)
Gold Prospectors Association of Tucson
Huachuca Mineral and Gem Club (Sierra Vista)
Huachuca Prospectors Association
Lake Havasu Gem & Mineral Society
Lake Havasu Gold Seekers
Mineralogical Society of Arizona (Phoenix)
Mohave County Gemstoners (Kingman)
Mohave Prospectors Association
Old Pueblo Lapidary Club (Tucson)
Prescott Gem and Mineral Club
Roadrunner Prospectors Club (Phoenix)
Sedona Gem & Mineral Club
Silvery Colorado River Rock Club (Bullhead City)
Sunsites Gem & Mineral Club (Pearce)
Superstition Mountain Treasure Hunters (Apache Junction)
Tucson Gem & Mineral Society
White Mountain Gem & Mineral Society (Show Low)
Wickenburg Gem & Mineral Society

Genesis 24:53

Gold in Arizona - A Prospectors Guide

The 2019 book edition on Amazon

Well, it took me long enough! Was beginning to think I would never finish this book on Gold in Arizona - but I did and it is now available at Amazon in both paper back and kindle. BUT, the paper back book is more up to date as I first tried my hand at publishing through Kindle (my first kindle book), and then after months of working with Amazons book templates (which were a pain in the neck), I finally finished a copy of the paper back book with updates, index, and additional editing. 

When I started writing this book, I was primarily trying to educate myself on Arizona's geology, which is different from the geology of Wyoming, Montana and Colorado that sit within, or long the flank of the Wyoming Craton (very old continental core). But I did have past experience in basin and range geology in Utah and New Mexico, where I had received part of my education as a geologist. 

The 2020 Kindle Edition

Thus, as I began compiling this book on Gold in Arizona, I never thought I would come across so many mines and prospects. Hundreds and hundreds - so many that I could not include them all in my 377-page book.

Actually, I could only get a limited sampling on mines because there are so many. What I did was look at the many, many districts and focused on the important characteristics and some of the more impressive mines. So, if you visit those districts on Google Earth, or by using the AZ Top Maps App on this blogspot, you will be taken to some of the more interesting mines that are listed with GPS coordinates in the book, and provided with ideas on how are where to prospect in these districts. 

Gold in an Arizona rhyolite 

One of hundreds of examples of detachment faults in Arizona. Note that
this one, like many others in the state, has a mine adit dug in the footwall
for gold. Both the footwall (the rock below the fault) and the hanging wall
 (the rock above the fault) may be mineralized in gold in these types of
deposits described in the book.

Is there any gold and silver in Arizona? You bet there is! Arizona produced considerably more than the 16-million ounces of gold and 500-million ounces of silver described in production statistics for the state.

In addition, there are relatively recently recognized gold deposits associated with what are known as detachment faults found over a giant region running from one side of Arizona to the other - and most of these are only partially explored with large regions remaining unexplored. And there are lots of the wet and dry gold placers. Yes, Arizona is known for copper, but it is also a significant source for gold.