Mineral Collecting – The Variety of New Specimens

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Legrandite Crystals

Legrandite Crystals

The average collector is hard put to add specimens to his collection today. They just cost too darned much. In the last few years the value of good specimens has skyrocketed far faster than the rate of inflation. There seems to be a number of reasons for this, not the least of which is the fantastic growth of the hobby, resulting in strong competition among buyers for the good specimens. This creates a seller’s market where price becomes secondary to acquisition. There is also a much greater awareness of Nature and Her irreplaceable wealth. New museums are being formed, the old ones refurbished. Private collectors are also moving into the “museum” circuit to get tax breaks and gain some degree of attention. As a result many people are decrying the apparent lack of good specimens, the dearth of material. When compared on a percentage basis I’m sure the number of specimens available vs. the number of good collectors would support this position. However, there is a bright spot on the horizon. As the value of specimens has risen dramatically so has the search for them. Over the last five years there has been an absolutely remarkable increase in the number of and variety of fine specimens. Given enough ready cash the average tor has had numerous opportunities to acquire truly fine pieces, pieces which in many ways are superior to older finds. These last few years have been bonanza times for collectors so are worthy of review.

With so many new mineral finds these last years it might seem difficult to determine a starting point for our report. Not so! Strange as it may seem we’ll start at a mineral show. Not just any show but the show that has consistently been the top show in the world, the annual Tucson Gem and Mineral Show. Held in early February each year for the last twenty years, this affair has grown such that it is considered by most experts as the best. Major museums the world over bring exhibits, the world’s top mineralogists are featured as speakers. Friends of Mineralogy, is an amateur/professional group dedicated to the preservation of minerals. The other, the Museum Curators organization, has been formed to promote cooperation among these important institutions. Even the federal government chose this Show to release the first information about America’s first Mineral Heritage Stamp. No wonder collectors and dealers alike try to attend and display their best at Tucson. Dozens of new finds are “saved” to be released at Tucson. The Show is so important and large that there are no less than sixty dealers displaying minerals in motel rooms near the show. In fact, at one motel there is actually a satellite show held in a large meeting room. An added point is the geographical locale. Tucson is at the hub of one of the great specimen producing regions, the Southwestern United States plus Mexico.

Words cannot express the importance of Mexico as a species producing source. Several of the truly great finds of the last decade have been made there, most often in old gold and silver mines. Among the spectacular species found have been legrandite, adamite, creedite, pyrrhotite, mimetite, wulfenite, boulangerite, and we could name a half dozen more. The color, variety and spectacular quality of these new finds needs no explanation.

Mexico has always been one of the world’s best sources of specimens and it continues to be so. Most especially has the old mine system around Mapimi been productive. It should be rated as one of the premier sources of mineral specimens of all times. In the last half dozen or so years it has produced two spectaculars, legrandite and adamite.

Adamite Crystals

Adamite Crystals

Adamite has long been a favorite from Mexico. If it had not been for the finds there, primarily at Mapimi, adamite would have to be considered a rare mineral. However, Mapimi has long produced an abundant supply of the bright green zinc hydroxyl arsenate. In the mid-1960s, however, the supply tailed off to almost zero. Then the big strike was made and literally several tons of material was uncovered and it was equal to the best ever found before. Plates of bright green crystals were dug out, some plates measuring well over a foot across. In addition, delicate fan-like sprays of crystals were sometimes found. Ranging in color from yellow green to lime green, this adamite was a bonanza on the specimen market for several years and is still to be found for sale today.

Mapimi Crystals

Mapimi Crystals

Mapimi also amazed the mineral world with a huge deposit of legrandite several years ago. Legrandite is a very rare mineral, or was until the big find at Mapimi. It had first been identified in the 1950s in small amounts from another Mexican mine. It is known that one mineral dealer had found a little legrandite in the Mina Ojuela at Mapimi in one of the lower levels. But, by the time he got it identified and hastened back to the search, the water level in the mine had risen so he had to wait. This rise in water level altered some of the legrandite so specimens today sometimes have that dull almost reddish chalky look from the bath they took. Once the water level dropped the legrandite zone was open and the specimens extracted were amazing. Bright yellow sprays of diverging crystals, some exceeding two inches, fanning out an inch or more across were found. Delicate single and small cluster sprays were also found. More rare were the very tiny complete spherical clusters forming complete “balls”. The largest of these exceeds an inch, probably the finest legrandite of its type known. Needless to say the specimen market exploded when the legrandite came out. There was literally a ‘rush” to Mapimi and prices soared. They have not come down since. Today, little of the choice legrandite of five years ago is available. The thousands on thousands of specimens have been absorbed into collections.

The rest of Mexico wasn’t idle while Mapimi was astounding us all. The old mines at Sierra de Los Lamentos were rejuvenated. As the price of minerals went up, collectors increased their efforts and new finds were made. So it was at Los Lamentos for a huge deposit of spectacular orange tabular wulfenite was found. They were unlike the nearly cubic orange crystals of the 1950s. Those showed a distinct zoning and nearly cubic habit. The new find still showed the zoning but to a lesser degree. The nearly cubic form gave way to a more distinctly tabular form of amazing beauty. Crystals two inches across were found. Clusters were so large that the strength of the collector sometimes determined the possible sizes involved. Cabinet specimens were more common than thumbnails. The luster on the crystals was so bright that shadows could be reflected in the crystal faces. These amazing orange crystals were scattered randomly on a white calcite onyx matrix, providing a marvelous setting for the colorful crystals. Many crystals were also found which were a deep chocolate brown rather than the bright orange. Just as lustrous, these dark brown crystals were heavily dosed with geothite inclusions, accounting for the dark color. They were found at the bottom of the solution pockets where waters had carried the geothite gouge to be trapped as the crystals grew. As is true of so much of the recent material, little can be found today on the market as collectors have swept the tables clean in their enthusiasm to acquire specimens.

Elsewhere in Mexico, creedite turned up at the mines of Santa Eulalia, noted for fine calcites. The creedites from here were the first macroscopic crystals of that species found in quantity. Some exceeded two inches in length, far surpassing the original microscopic crystals from Creede, Colorado.

In addition, these exceeding sharply terminated crystals were amethystine in color on most of the specimens. The crystals were usually in divergent sprays, some forming dome-like halfspheres. As I get the story on their original discovery, Paul Desautels from the Smithsonian was handed a specimen of these then unidentified crystals. The lighting was bad but based on the sharpness of the minations Paul suggested the material would be proven to be creedite. This anecdote suggests the skill of Mr. Desautels, our highly respected mineralogist from the Smithsonian.

On a smaller scale, but not less important to the collector of rare specimens, came a find of greenish milarite crystals from Guanajuato. That old silver district, one of the oldest in Mexico, is still producing for collectors. The milarites occurred as single crystals, seldom exceeding a half inch, embedded in a white crystalline matrix.

Pyrrhotite

Pyrrhotite

A couple of other silver districts in Mexico have been responsible for a fabulous amethyst quartz these last few years. Fine plates of gemmy amethyst, associated with green epidote, has come from Santa Cruz. The crystals are gem-clear and often start at the base as clear quartz but develop an intense amethyst color toward the tips. They seldom exceed an inch in length but some of the more spectacular pieces have crystals larger than two inches. The crystals jut out at random from a common point, forming truly fine display pieces. Amethyst from other sources, Guerrero and Guanjato, are not as bright and colorful but are excellent nonetheless. The Guerrero crystals often exceed six inches in length and are quite showy.

It would seem that Mexico has done its share of adding to the mineral realm with what we’ve mentioned so far. Such is not the case, however, for more was forthcoming in these last few years. Most colorful but massive was the botryoidal yellow mimetite from San Pedro Corallitas. Found in a wide seam of an old gold mine, this material was extracted in huge masses and amounts in 1970. The first I heard of it was a call from a mineral dealer in Tucson, excitedly reporting the arrival of seventy five crates of the beautiful material. Needless to say, I dashed to see it and was rewarded with a wonderful sight, table after table and box after box of fine lustrous grape-like masses of bright yellow material. More was mined immediately and the supply was generous to say the least. Again, it has dwindled to nothing as the vein played out.

Less colorful but amazing in their crystal size were the white hemimorphite crystals of a few years ago. Some of these giants reached three inches long. A few were enhanced with a reddish iron staining, particularly heavy around the base of the crystals. These were found in the Santa Eulalia mine and eclipsed anything that had been found at Mapimi to that time.

There have been many other finds in Mexico these last few years, among them the gem-clear scalenohedron crystals of rhodochrosite, some brilliant and sharp arsenopyrites from Noche Buena, and the gray needles of boulangerite (initially labeled jamesonite) from the same place. The amounts of these were limited somewhat so their impact on the specimen hobby was limited as well. The same may well be the case of the recent finds of pyrrhotite from Santa Eulalia. The earlier find, within the least three years, produced huge crystals, some stacked as high as six inches or more and a few exceeding that amount in cross section. A later find at the same mine has produced exceedingly sharp and bright smaller hexagonal groups of crystals, among the finest ever found anywhere. Time will tell if the supply will be sufficiently large to have a significant impact on the hobby. Meantime, every effort is being made to extract more of these metallic beauties.

In concluding our discussion of Mexico’s recent contributions I chose to treat the spectacular orange wulfenite and red mimetite from an old gold mine, Mina de San Francisco, Cerro Prieto, Mexico. This old mine is a deep one, as are most of the mines of Mexico. This is possible because the dryness often means great depths can be reached without encountering the water table. It also allows surface waters to penetrate deeply, carrying oxygen and altering the primary ores to create secondary minerals of unmatched beauty. Such is the case at the Mina de San Francisco, where orange wulfenite have been found. These wafer-thin crystals are clear enough to read through and have been found exceeding four inches on an edge at the mine. Currently, the search has stopped for the price of gold has gone up and the gold vein is being worked. Hopefully, the lead vein, where the wulfenites are found, will be opened again. The specimens of the last two years came from as deep as 1200 feet in the mine. The first pockets encountered yielded a pale yellow wulfenite of modest size. Later pockets began to produce larger and more orange colored crystals. The ‘last pockets opened were lined with huge clear orange crystals. Stuffed down between and on these wulfenite blades were lustrous deep orange-red balls of mimetite, making these specimens some of the most attractive wulfenites ever found. The quantity was considerable, numbering in the many dozens of boxes. Once the search resumes there is no reason to believe more will not be found. Truly, this most recent find in Mexico has had an impact on the specimen market and will do so again once activity resumes.

Hubnerite Crystals

Hubnerite Crystals

Farther south, in the countries of South America, specimen production was having an impact on the market. Certainly Brazil vas continuing to make major contributions. A “new” source was heard from as well. Peru produced spectacular octahedral pyrites once again. In addition, it yielded, to the adventurous, the finest terminated hubnerites ever found. The pyrites show interesting growth patterns on the faces, which are brilliantly shiny. The octahedral crystals were sometimes very large, some rumored to be up to seven inches high. The source for these magnificent sulfides was Quiruvilca. The hubnerites, a deep red color, were associated with quartz crystals, often being nearly completely coated with the quartz. That could be removed, however, revealing sharp, perfectly terminated tabular blades of the tungsten mineral. The mine, situated in spectacular but dangerously remote territory, is the Huyallopn. Several days of jeep riding, sometimes clinging precariously to the wall-like sides of high mountains, were required to reach the mine. For those few who made the trip I guess it was worth it.

Brazil is always producing something. There .are so many gem deposits, rotten decomposed pegmatites, and mines of all types, that there’s always something new. Surely, the supply of gem tourmaline, morganite, aquamarine, and other pegmatitic gem material hasn’t slowed. And, in a few cases, has been quite spectacular. The huge green tourmalines from Santa Rosa were amazing for size and form. Their blue-gray tips only added to their beauty.

We are interested here, however, in the unusual finds of specimens that collectors dream about. Most limited of these was the find of some amazingly large wardite crystals along the Jequitinhonha River, near Taquaral, MG., Brazil. Wardite is a rather common phosphate, particularly in the massive nodules of varied phosphates found at Fairfield, Utah and elsewhere in that state. No one, however, was prepared for the huge, up to an inch, crystals stumbled on at this old pegmatite by an American dealer. Again, the value of minerals had risen enough to encourage free-lance traveling to stir up the specimen sources. Once found, these crystals were returned to the States for identification and immediately attracted considerable attention as being the largest wardites ever found. Their discovery was a spinoff of an earlier find of magnificent rose quartz crystals pleasingly dressed with a scattering of rare phosphates. The mine, located on an island in the river, is a completely decomposed pegmatite. It can only be worked at low water, and in fact is not being worked at all today. The rare phosphates found include bright brown sprays of eosphorite with crystals averaging near a half inch, roscherite in radiating half balls of greenish crystals, and one or two other less important phosphates. These minerals are fine by themselves but to be scattered profusely on bright pink terminated quartz crystals, some of which were over two inches high, was just wonderful for collectors. The rose quartz was not in free standing groups but in sub-parallel sprays showing excellent terminations. Sometimes the rose quartz was little more than a lustrous druse on which the eosphorite and other minerals formed. Nonetheless, they were aesthetically beautiful and mineralogically interesting so attracted much attention at shows.

Europe has added its share to the mineral market this last decade. The two most notable finds have been the tungsten and associated minerals from Panasquçira, Portugal and the delicate sprays of stibnite from Romania. Both finds were first brought out by the same team of dealers. the Panasqueira minerals have been spectacular in size and variety while the Romania stibnite has been found mostly by itself or associated with excellent barite plates. The Portuguese find produced wolframite in black, lustrous crystals sometimes several inches across and four or five inches long and longer. These were often associated with iuartz and coated with siderite, which could be removed easily. In addition, deeply zoned, fine green apatite crystals occurred there in plates of several inches across. In fact, the largest of the apatite crystals were several inches across themselves. Lustrous plates of arsenopyrites were also brought out of Panasqueira at this time. The crystals show the typical habit of arsenopyrite, are silver colored, and sometimes exceedingly bright. One inch crystals are common and plates to a half a foot across not unusual. The fourth notable mineral from here is the cassiterite, found as small brilliant crystals embedded on quartz. These crystals, usually dark brown, were often twinned and intergrown. Their remarkable luster and association with quartz crystals made them very desirable specimens.

Romanian Stibnite Crystals

Romanian Stibnite Crystals

The Romanian stibnites were the first significant specimens, for quality and amount, to be brought from behind the iron Curtain. The crystals are acicular to the extreme, usually being less than a quarter inch thick and sometimes reaching five or six inches long or more. The exact locality name has been given as Felsobanya, Kysbanya, Baia Sprie, and elsewhere. All these names apply to the same general deposit. What is more important are the marvelous sprays of crystals, often intersecting with other sprays to form a tangled geometric mass of spectacular appearance.

Spain has also added to the storehouse of minerals which dealers have had to offer these last years. Lustrous, nearly clear white to clear to gray rhombs of dolomite have come from Eugui. Often twinned, these rhombs sometimes exceeded four inches across and were sharp and bright. They rank among the finest dolomites in crystal form. Spain also has produced excellent pyrites, seemly being an almost endless source of that attractive metallic mineral. Fine singles well over an inch across, sometimes in matrix, have been coming from Spain recently. The supply of aragonite pseudo-hexagonal crystals also seems to be endless. The latest are even more beautiful than usual, being deeply colored purple around the middle of the crystal and nearly colorless on the ends.

Moving into North Africa, we must make note of the spectacular vanadinite crystals coming from Mibladden, Morocco. Found in a crumbly sandstone-like matrix, these hexagonal beauties are truly amazing crystals. They range in color from brilliant red to deep lustrous brown. In the vanadinites from the U.S. at the Apache and Old Yuma mines crystals tend to grow up to a half inch on an average, the Mibladden crystals seem to start there and go over an inch. They tend to intergrow, forming flower-like arrangements of crystals seemingly incorporated into one. Often the prism faces are dull and lighter in color but the main terminations are brilliant and usually a marvelous color. Only a few specimens appeared on the market at first. But as interest grew so did the volume of specimens, relfecting the increased mobility of some dealers. They flew into the region, acquiring large amounts of specimens. This attention has stimulated the appearance lately of other minerals, azurite and cerussite to name two.

Elsewhere in Africa, new finds were being made. The most spectacular would probably be the new gem mineral tanzanite, not a new mineral at all. It is simply the finest gem grade zoisite ever found so is given a new marketable name by gem dealers. The crystals found have reached two inches, sometimes being an inch thick. The color is normally a deep blue but can be dulled. The crystals also show dichroism, changing color in different lights. So, it may surprise you to see a blue tanzanite suddenly seem Co emit a reddish color due to this. The hope for this gem material was that it would be found in sufficient supply to create and supply a whole new gem market. Such may not have been the case, however, for the source soon dried u to the point that stones have become almost a mineral curiosity. The first crystals were found in the early 1960s in Tanzania and a “rush” developed. The Smithsonian was fortunate enough to acquire, early in the game, a fine 123 carat stone, again due to the alertness of Paul Desautels.

Cuprian Adamite Cyrstals from Tsumeb Namibia

Cuprian Adamite Cyrstals from Tsumeb Namibia

Tsumeb, in South West Africa has not stopped producing surprises either. Decades ago that mine produced fine, sharp, deep blue azurite crystals but nothing had been found of the earlier quality recently. However, a couple of years ago miners did locate and remove some spectacular azurite crystals in small groups from an old pillar at the 900 foot level. Needless to say, these specimens brought premium prices on the recent market. Tsumeb also yielded a new mineral of note. It was only found in one specimen, a vug containing a bright reddish brown spray of hairlike crystals to four inches long. It was finally identified as being new and named after two mineral dealers who have been responsible for bringing to light an inordinate number of the mineral finds we’ve noted here. The mineral is called ludlockite, one of the rarest of display minerals.

Not to be outdone, the uranium mines of Zaire blossomed forth with a spectacular find of green torbernite blades recently. Other rare uraniums have come forth from elsewhere in Africa, among them francevilleite and chervetite, but nothing compared with the stunning masses of deep emerald green torbernite blades from Musonoi, Zaire. Wafer-thin square crystals over an inch on an edge, found in masses a foot and more across have come out. Their emerald green color and fine quality have made them among the best torbernite ever found. Keep in mind at this point, however, that all secondary uranium minerals tend to lose moisture when exposed to the atmosphere so these rightly should be considered to be meta-torbernite.

Other relatively small amounts of minerals have come from Africa. The roselite and other minerals from Mibladen and the fine bright red groups of gemmy rhodochrosite from Hotazell, SW. Africa. Nothing compares with the recent find of cuprites at the Emke mine, Onjanja, SW. Africa. We’re familiar with the usual druse of red cuprite crystals. Sometimes someone, in Arizona particularly, may even see a specimen of cuprite with a crystal over a half inch. This makes the TWO INCH cuprite cyrstals from this mine that much harder to believe. They are amazing. Found very close to the surface in a relatively unimportant mine, these crystals are coated with green malachite when removed. They are sometimes cleaned but the faces remain pitted. They are all gemmy or nearly so, which means many will ultimately be faceted into brilliant, deep red, but soft, gem stones for display. These cuprites rank as one of the great finds of the first half of this decade, being the largest ever found and, probably providing some of the largest gem rough ever known for this mineral.

Australian Crocoite Crystals

Australian Crocoite Crystals

Australia’s contribution recently has been more fine crocoite from the Dundas region. There are a number of mines in that area, all produce crocoite in greater or lesser amounts. As the hobby grows in that great country there will be more of this mineral found, as have been evidenced already by finds in the early 1970s. In huge quantities and sizes have come the brown dravite variety of tourmaline front Yinnietharra, in West Australia. Sizes from an inch or so up to something that looks like a fireplace log have been found. I’ve been told some of the crystals are too large for the average collector to handle easily and am inclined to believe this is true when I see what has been brought to the States. These excellent display and study crystals are found embedded in a schist-like material so can be easily removed intact and are almost always well formed, sharp, and terminated. They lack brilliant luster due to minor inclusions of the host miceous material but are, nevertheless, spectacular in size and form.

We could continue with descriptions of rare finds, limited finds, unspectacular finds, but by and large we feel the above pretty well summarizes what has been going around the world these last few years. We have said nothing of the semseyite of Romania, the fine wire silver from N.W. Territory of Canada, the Scholzite from Australia, and many other fine discoveries which have added their bit to the hobby.  It is important to remember, however, that somewhere, whether it be in San Francisco, other U.S. cities, or elsewhere in the world, some collector, some dealer, some miner, is gathering specimens right now which may very well become the next big find. So, as you complain about prices and specimen values, remember that it is this economic stimulus which has brought the mineral hobby from the “small time” into the world of big business. Like it or not, it has created supplies of noteworthy minerals, some of them the best ever found, simply because the economics were right. There is no reason to believe that will change. Something new is just around the bend, just down the next tunnel. Why not go find it?

Mineral Collecting – The Variety of New Specimens, 9.7 out of 10 based on 9 ratings

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