BEAUTY FROM THE EARTH

On Mineral Collecting in Arizona BEAUTY from the EARTH

Earlier this year an editorial in a Phoenix newspaper contained this statement: "Among the most generously rewarded desert prowlers are the 'rockhounds,' those who collect and study rocks instead of merely crunching them underfoot." On the desert floor, the moderate slopes of outlying foothills or in the roughest mountains there can be found exercise, entertainment and education among the rocks.

There are different kinds of rockhounds. Some collect rocks and minerals (they are different, you know) for their beauty. Others are thrilled by the natural symmetrical forms, called crystals, which many minerals assume. Some collect and study them for their economic importance. Others are curious to know what they are made of and how they grew. Some are delving into the composition of neglected rocks hoping to discover a secret by which the mineral may be made to contribute something new to our well-being, comfort or our convenience. Finally, there are those who envision within the rough stone a sparkling jewel for milady's adornment or a carved object of great beauty. Whatever the incentive to collect and study rocks and minerals, there is a lasting reward in knowledge, health and happiness.

Though the word “rockhound” is comparatively new, born of the tremendous renewed interest in this branch of the earth sciences during the past twenty-five years. Collecting minerals for one purpose or another is older than written history. Gemstones used for ornament, or some ritualistic purpose, were collected centuries ago. In Arizona, excavations in prehistoric dwellings, occupied and abandoned hundreds of years before the coming of Europeans, have yielded assemblies of colorful stones in a studied and orderly arrangement. The true significance is CAMERA DATA Photographing minerals in color is an art. Floyd R. Getsinger, who took the color photographs of minerals in this issue, is an expert in this field of photography. His lengthy discussion of his specialty begins on page 15.

Though the word “rockhound” is comparatively new, born of the tremendous renewed interest in this branch of the earth sciences during the past twenty-five years. Collecting minerals for one purpose or another is older than written history. Gemstones used for ornament, or some ritualistic purpose, were collected centuries ago. In Arizona, excavations in prehistoric dwellings, occupied and abandoned hundreds of years before the coming of Europeans, have yielded assemblies of colorful stones in a studied and orderly arrangement. The true significance isnot known but, since these bright stones could not be used for either a tool or a weapon, they must have been selected for a purpose, especially since they occupied a place of honor. As a hobby, mineral collecting now has a greater following than ever before. There are two reasons, important but not necessarily the only ones. First, we in this country now have more leisure than ever before. Secondly, the transportation problem confronting the collector of half a century ago no longer exists. On a weekend you may take the family to a remote field, collect leisurely and return home laden with plunder, enriched by the time spent in the open and prepared for the busy week ahead. What is it that is the outstanding characteristic of Arizona minerals which captures the attention of both laymen and the collector? It is color. Arizona is famous for its colors, colors in shades and hues and tones, changing in kaleidoscopic fashion, in the mountains, on the desert and, above all at the Grand Canyon. It was color that brought the famous artist Maxfield Parish to Crown King to learn more about color. The most lasting and vivid remembrance the visitor has after returning home is the appreciation of color. Touring a museum, even if doing it against time, your attention is arrested immediately when passing a display of Arizona minerals. You pause instinctively entranced by color. For certain minerals the colors are standard or nearly so. The shade or brilliance may vary. Copper is the most important metal in Arizona mining economy. The characteristic surface expression of copper is green, sometimes mixed with blue. A small amount of copper in this oxidized form will color a large amount of rock; so it is not uncommon to see large exposures of green stained rock with perhaps streaks of blue and always some red. The red is an indication of the iron originally combined chemically with the copper. Exposed to the powerful agencies of erosion, the original minerals have undergone considerable change in form, composition and color. Lead minerals also undergo changes which produce brilliant hues of yellow, orange to red. Much of the beauty of the end product of erosional changes in minerals is due in part to the peculiarities of our climate. "Where to look for what" is the first question which comes to the mind of a rockhound in Arizona, whether he be a native or a visitor. There are many answers. First, you have guide books, some not too elaborate in format but with roads, mileage and "X marks the spot." Other guides there are, substantially bound giving in addition to the description of suitable collecting localities a bit of history, a legend or some other item of local interest to enliven the reading. There are magazine articles too, some with maps, some without, and with the necessary "X marks the spot." The hobby magazines as a rule give excellent directions, and most mineralogical societies have regular monthly field trips. The members are always ready to assist beginners or strangers to choose a locality in which to hunt. Few rockhounds, especially beginners avail themselves of the many valuable helps to be found in the publications of the Ú. S. Geological Survey, the U. S. Bureau of Mi Mines, as well as the publications of own Arizona Bureau of Mines. To a beginner these various reports may seem formidable but just a little study will indicate what parts are of real value to the rockhound. In almost every instance there is a section devoted to the mineralogy of the area. In some U.S. Geological Survey Bulletins and Professional Papers not only are the minerals listed but there are elaborate descriptions of the special types met with in the area. Rockhounds will do well to become acquainted with these sources of valuable information. It is not necessary to read them from cover to cover, the index will indicate just what parts are most interesting to rockhounds. our There is another way, much more exciting than following the personally conducted "tailor-made" field trip found in a guide or magazine. If there is a bit of the pioneer in your make-up, if you are self-reliant and can become enthusiastic over a personal new discovery, you are on the way to thrills not experienced by the collector who needs to be taken by the hand and led to the spot. Of course it is not as simple as following a detailed route to find "X" but it provides two things not available through these guide trips-anticipation and realization. There is a great deal of satisfaction in deal of satisfaction in being the first to find a new locality or a new mineral in an old locality. An eminent mineralogist who, more than thirty

years ago prepared an elaborate first hand report on the mineral localities of an eastern state, said recently, in a public address, that it is possible still to collect good specimens in those old localities. He challenged his audience to visit some of the areas, sometimes spoken of now as worked out. He promised them they would be rewarded if they were diligent. He said the first and most important requisite for this type of collecting is enthusiasm and a will to work. The collector who demands to be accompanied by someone to carry his pack is not going to be successful. The next important requirement is some practical knowledge of elementary geology, coupled with the realization that minerals are choosy about where thev come to rest and just as particular about the company they keep. A little knowledge of geological formations, with emphasis on those favorable to certain types of minerals and why certain minerals are associated, will save miles of travel and hours of unrewarded search. If you want shoes you do not go to a grocery store; if you are looking for pegmatite minerals don't search in vast areas of sedimentary rocks. It has been pointed out that all Arizona is not desert. There are three physiographic provinces recognized by geologists. Across the northeast is the Plateau Province; crossing the southwest is the Desert Province. Between these two, forming a graceful "S" bend is the Mountain Province. This zone, averaging one hundred miles in width, crossing from the northwest to the southeast is narrowest in the northwest. At the other extremity it turns more to the south and widens as it crosses the border into Sonora, Mexico. Here begins another extensive and well mineralized area, practically unknown to collectors. Conditions are changing below the border; some day perhaps rockhounds may collect there the gorgeous peach-red erythrite, the tawny scheelite crystals some of which weigh as much as a pound, the feathery stibnite and so on, a long list of minerals any collector would cherish as additions to his collection. Until the beginning of the uranium boom the plateau province was not an attractive field for the mineral collector. In the very northwest corner on the far side of the Colorado River, accessible only from Nevada, were a few copper mines never profitable though one could claim some attention because of the peculiar shape of the ore deposit. It is different now; the plateau is humming with activity of uranium mining. Roads and bridges make travel easy. There is the blood-red metahewettite as well as the old stand-by canary yellow to greenish yellow carnotite. Despite its name tyuyamunite, also yellowish, less common than carnotite, is interesting specimen material. Rabbetite and Collinsite are "bragging rocks," known only in specimens of a fraction of an ounce weight.

Carnotite as grains and tiny crystals in petrified wood are choice items especially if the wood has a cavity filled with jet black, needle-like scintillating crystals of manganite or, more rarely, blue or brown barite. With such treasures in the offing the lead minerals in Havasu Canyon are no longer exciting. However, the trip to this hidden wonder spot is never to be forgotten. The glamor of pyrope garnets and peridot around Ft. Defiance also dull before the possibilities of the known uranium minerals and those new species which are bound to be discovered.

Let's hop over the mountain province, leaving that for later consideration. If the word "desert" fills you with misgiving, causing a creepy feeling, it is the very place you should visit to discover how misinformed you are. The minerals are not too important but the desert is full of wonderment; things other than minerals. Any rockhound who has seen the gorgeous crystals of wulfenite from the Red Cloud mine north of Yuma would be happy to have just one nice specimen. In this same little frequented area there are other lead and silver minerals as well, not too abundant but well worth the effort to find. Nearby at Castle Dome pink, purple and white fluorite, secondary lead minerals, galena, blocky and bladed barite may be collected. In other parts of Yuma county there used to be good collecting but much of it is now closed having been appropriated by the Army for one purpose or another.

If you have never paused to examine critically the smooth, pebble-paved desert floor you have missed something. First, consider the nature of the surface; closely spaced dark colored, smooth faced pebbles. Between them is a minimum amount of space filled with tightly packed grains of sand. Pry up one of the pebbles. The bottom may be irregular or smooth but it is bound to be of a different color from the exposed surface. Why? Moisture and sunshine working together have given the surface a thin coating of iron-manganese oxide, aptly called desert varnish. The upper surface whether rounded or angular is kept polished by the tiny sharp grains of windblown sand.

Next examine the spot from which you removed the stone. It is very light colored, standing out in striking contrast to the surrounding dark mosaic. Here we have the elements for expression of artistic talent by prehistoric peoples which very few Arizonans have seen. By removing the dark surfaced stones systematically the white below will form a picture, a human figure, an animal or crude geometrical design. The few examples of this rare art are usually on an extensive scale for which reason they may be overlooked. This makes it more difficult to understand how these ancient people could create such a picture fifty to one hundred feet square working at ground level. From a low-flying plane such designs could be seen distinctly but there were no planes in those days.

The pictographs you see pecked into the dark surfaces of boulders, large and small, on the faces of cliffs of "malapais" rock and less frequently in caves are possible because of the dark layer of desert varnish. There are several "don'ts" to be observed in connection with pictographs. Don't try to improve on the artist's original work. Don't deface even the poorest example. Don't carry away as a whole or any part of the material. In fact regard them with the reverence they deserve. Finally, for purposes of photographing, don't chalk over the design. Itdoes not injure the drawing, thanks be, but it spoils your photograph. Demonstrate your skill as a photographer and get a fine picture without the use of chalk. It can be done.

Moving south into that real desert south of the Yuma area, traversed by the early missionaries, California bound from New Spain to establish missions, there are limited collecting possibilities. It is not necessary to follow the famous El Camino del Diablo; its tough and nothing to see but the relics of travelers who perished on the way. It is safer and easier to go to Gila Bend thence south to Ajo, which is the most important settlement in the area. Southwestward and crossing the border are the Pinacate Mountains where chatoyant feldspar may be found. South of Ajo, the rare mineral elpidite occurs in the Organ Pipe Cactus National Monument. To the east in the Growler Mountains, near the border and east of Papago Well, are pegmatite dikes with some rare-earth minerals. You really hunt for the specimens but they are there. The huge open-pit mine at Ajo is not open to collectors but there are many prospects near by. Chalcedony and jasper occur on the desert floor. Eastward across Pima County there are known localities of tungsten, lead, copper and silver minerals; aurichalcite, rosasite, fish-tail barite crystals, tourmaline and beryl so the desert province is not devoid of interest for the rockhound. You just have to hunt harder. You don't pick up specimens as easily as you can on the counter in a rock shop.

Before entering the mountain province where most of the mining is carried on it is appropriate to make a few remarks about mines, prospects, property and people. Every opening, even no more than a few feet deep, is evidence of private property. If abandoned now it was once someone's mining claim, his private property. If there is evidence of recent activity you should make an effort to determine the ownership and secure permission to collect. You would resent it if someone came into your yard and started carrying off your rock pile. If there are buildings, you have no right to enter. If there is equipment, including tools on the property, none of this is yours; so leave it alone. In short, you are a visitor. In recent years there has been a tendency to ignore common courtesy by mistreating the property of others. If this is persisted in, such conduct will dry up forever all collecting areas about mines and prospects. Keep your place, be on your good be-havior and no one will resent your presence.

If you enter Arizona from Nevada via the Hoover Dam, you will be in the very northwest extremity of the mountain province. Along the Nevada line the zone is about sixty miles wide. The first opportunity to collect is only a short distance from the dam. Hurrying along the highway very few people notice a conspicuous dike crossing the road and showing on each face of a deep cut in the alluvium. In the gray groundmass of the dike are sizeable crystals of kaersutite, a rare titaniferous amphibole. Off the road on either side are larger crystals in the dike. The sides of the cut are almost perpendicular across which the dike makes a conspicuous band. It is about seven miles from the dam. On the river side of the highway there is agate and jasper.Passing the ups and downs through more cuts like a roller coaster course, the road emerges into the broad Detrital Valley flanked by mountains on either side. These mountains are strictly virgin territory as far as rockhounds are concerned. A few very old mines produced a little long ago but are abandoned now, White Hills area in particular, and there are lots of prospects. Gold, lode and placer, silver (White Hills) wulfenite, uranium minerals and who knows what else have been found or will be in those mountains. In sight from the highway, if you know just where to look, opposite Chloride, there is endlichite in a shallow prospect. The whole west side of the Cerbat Mountains, south almost to Kingman, is a heavily mineralized area. From Ithica Mountain came Arizona's finest turquoise. On the opposite side of the range there are good collecting possibilities little known to rockhounds.

It should be kept in mind that the boundaries of the mountain province are generalized rather than definite. Frequently in the fringe area there is good collecting for the whole province is peppered with prospect holes, and practically all the important mines of the state are in this belt. The large producing mines are not open to collectors but in the immediate vicinity of each there are opportunities to find good specimens. The dumps of many old mines, now abandoned, still hide some choice material.Annual mineral show at State Fairgrounds in Phoenix is popular event attracting thousands of interested people.

As an aid to “where to look for what” it may be helpful to know the way the common minerals are grouped or associated. From the economic point of view the most profitable minerals in Arizona are the copper minerals, of which there are more than sixty species. Some are rare, seen only in museums; others occur in such minute quantities that they are easily overlooked hence difficult to find. The more important copper ore minerals are abundant and because of their bright colors are easily seen. Mineralogists differentiate between the primary minerals, those found in their original state, and the secondary minerals which have been changed in form, color and composition. This alteration almost without exception yields brighter colors. Lead minerals too undergo change which produces a variety of Conspicuously bright colors.

From this brief resume, touching only the high spots as to localities and types, it is not at all difficult to understand why rockhounds dream of collecting in Arizona, of having choice specimens from the pegmatites as well as from the veins of copper and lead. There are some three hundred species identified in Arizona. To make a complete collection, including the new ones as they are discovered, is a worth while goal for any collector.