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In past issues of our newsletter I have published bits and pieces gleaned from the pages of old geo reports that I come across from time to time. They can make fascinating reading, especially the older ones that skip the scientific prose and can read like your average fossicking trip! A couple of years ago Ron Young gave me a piece for publication that was written by Corbould and described the crystal caverns to be found in the Mount Elliot mine in Northwest Queensland. This fabulous place is famous for its huge gypsum 'selenite' crystals that were metres long and transparent. Inside bright native copper dendrites were clearly visible throughout. A number of these are preserved in the Queensland Museum, from when the old Geological Survey collections were transferred. They were collected around 1910-1915. Also mentioned was the story of a dragonfly wing found preserved in one of these selinites, that belongs to the Australian Museum.
Recently I was browsing some old issues of the NSW Geo survey records and came across an article about this very subject, and interesting it is! The following article is extracted from:
Records of the Geological Survey of New South Wales Volume X, Part II, 1922
V.—An insect wing in a Crystal of Selenite (Order Orthoptera) ; by R. J. TILLYARD, M.A., Sc.D. and &c., Nelson, N.Z. (Plate XV and text-figure)
" The fragment of an insect’s wing, which forms the subject of this paper, was discovered in 19... in the Mount Elliott Copper Mine, North Queensland. It was found at a depth of 260 feet below the surface-, embedded in a large crystal of selenite enclosed in the actual copper lode worked by this mine. It is, therefore,, the only fossil insect wing ever actually found in a mineral lode.
The lode in which the fossil was found is almost vertical, and outcrops through slate country. At the point where the fossil was found the lode is 120 feet wide, the position of the fossil itself being about eighteen feet from the footwall, which is here almost vertical. The actual crystal of selenite in which the fossil occurs is a beautiful specimen, very clear, but tinged with green and brown ores of copper, on the slant faces, and also on the edge closest to the fossil. Thickness of crystal, 20 mm. Upper surface a rhombus (approximately) on a side of 75 mm. ; angle 65'. Under surface roughly a parallelogram, sides 40 mm. and 85 mm. ; angle 65'. The fossil lies embedded about 2 mm. below the upper surface of the crystal.
This fine specimen was forwarded by Mr. Corbould, Qld., manager of the Mount Elliott mine, to the Geological Survey Branch, Department of Mines, Sydney New South Wales, and is now in their Museum. 1 desire to thank Mr. W. S. Dun of this Department for his kindness in giving me the opportunity of studying this fossil, and I also thank him and Mr. Corbould for so readily supplying me with information about it.
It would seem that the most probable explanation of the occurrence of this wing-fragment in so remarkable a position is as follows: -
At the time of the formation of the copper lode, or shortly afterwards, large vugh channels must have existed, reaching to the surface of the outcrop. Down these, water percolated; and the wing, quite probably in its present fragmentary condition, as part of the remains of some dead insect, was either blown or washed into one of these channels, and carried downwards until it reached a resting place in some out-of-the-way corner. Here it became incorporated in some manner between the layers of crystallising selenite that have been found in several parts of the mine embedded in the lode material.
Under these circumstances, it is of course impossible to assign the fossil to any definite geological epoch. All we can say is that the lode is older than the fossil, since the vugh channels must have been formed either by the cooling of the lode or by percolating waters. Also, these channels may have remained open for centuries, and the deposition of the gypsum crystals by minerally charged waters dripping from above may in itself have been the slow work of many years. Even though the lode itself might date back to the Paleozoic era, the age at which the deposition of the gypsum crystals took place, might still be only Tertiary. In order then to arrive at some definite conclusion on this matter, we can only fall back upon the evidence afforded by the fossil itself; and this, as we shall see, is fairly definite.
The conclusion which I have reached after a very careful study of the fossil is that it is an archaic type belonging to the family of Long-horned Grasshoppers (Tettigoniidee or Phasgonuridae, formerly called Locustidee), and that it does not belong to any genus known to exist in the world to-day. Mr. A. N. Caudell, the well-known Orthopterist of the United States National Museum at Washington, to whom I submitted a drawing of the fossil for expert opinion, has replied that ‘among recent genera, I know of nothing to which your insect can be referred.’ A careful study of known fossil Orthoptera indicates that, this wing is more highly specialized than any known Mesozoic type. This indicates that the fossil should be considered of Tertiary age, and preferably somewhat late Tertiary, in so far as it appears to be more closely allied to recent Long-horned Grasshoppers of the subfamilies Phasgonurinae and Conocephalinae than to anything known amongst fossils.
It is very unfortunate, from the point of view of paleontology, that so little use of the wing-venation has been made in the classification of the Orthoptera. The origin and relationships of the different venational types within the order are at present little understood. While excellent figures of the parts of the body used in classification are to he found in hundreds, yet very few reliable figures of the venation can be found, even in such standard works as the ‘Genera Insectorum.’ The comparison of the venation of the fossil had, therefore, to be made with such Australian, New Zealand, European, and American material as has been available to me. Fortunately, this includes a large number of types ; but I have not been able to find anything at all closely approaching the venation of the fossil. I have, therefore, decided to erect a new genus for it, and to place it definitely within the family Tettigoniidae, possibly as the only known representative, of a Tertiary subfamily now extinct, but closely allied to the Phasgonurinae and Conocephalinae.
The new species is dedicated to Mr. Corbould, who may be regarded as its discoverer, in so far as it was through, his endeavours that the specimen was saved from destruction and sent to the Department of Mines in Sydney. "
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(Museum of
Northwest Queensland, PO Box 1472, Mount Isa, QLD 4825)
This Paper was presented to the 20th Joint State Mineralogical
Societies Seminar held in Brisbane in June 1997
The Mount Elliott Mine was discovered around the turn of the century. It is in the Selwyn Range about a hundred kilometres south of Cloncurry in northwest Queensland. Mining there commenced in earnest with the formation of a company, Mount Elliott Limited, which appointed the almost legendary W.H. (Jimmy) Corbould as mine manager in 1909. He was to guide mining and production successfully throughout the years of the first world war. Operations in those days were limited to the oxidised ore in the upper 100 metres or so of the lode, which was amenable to treatment by the elementary furnaces of that time. By 1919 copper prices were falling all over the world, and when this was coupled with industrial unrest in that remote region, the mine was closed down in 1922. Since 1992, Australian Resources Pty Ltd (ARIMCO) has operated the Mount Elliott Mine, where they have extracting sulphide ores, for production of a chalcopyrite concentrate with appreciable gold content. They are currently at a depth of 290 metres, and expect to continue operations for about five more years.
The Mount Elliott copper orebody has strong similarities to a traditional contact metamorphic deposit, but produced in this case within a grossly brecciated lime-rich skarn host rock during an epoch of moderate metamorphism. An adjacent granite could have been involved in its formation. Considerable hydrothermal activity and lime metasomatism has produced a suite of distinctive minerals in close association with the orebody. Calcite is consequently a major component of the primary ore, and includes masses of chalcopyrite which may occasionally be several metres in width. The calcite is a bright pink colour from minute inclusions of haematite, and is usually very coarsely crystalline. The wallrock is metamorphosed in many places to a fringe of blocky well formed crystals of the pyroxene, diopside. These crystals are of exceptional quality for what is in reality a very rarely crystallised mineral even by international standards. They are frequently of very considerable size, but difficult to collect as they occur in clusters which are most commonly enclosed within the pink calcite. Apatite and scapolite are also commonly well crystallised components, apparently produced by metamorphism in conjunction with the diopside and calcite. The chalcopyrite seems to have been concentrated into voids in the core of the ore zones in a late more hydrothermal spasm of mineralisation, which frequently developed vughs lined with crystals of quartz and calcite. The quartz is frequently a delicately tinted amethyst variety producing geode linings of great beauty. These later generations of calcite show an incredible range of colours and forms, and in some instances are crystallised in geodes with the amethyst.
Copper mines in the Mount Isa-Cloncurry region are all notable for the development of quite deep zones of oxidation and supergene enrichment. Mount Elliott is no exception, cuprite, malachite, azurite and chrysocolla, were originally common in the oxidised zone, with an unknown assortment of other species. Virtually all the oxidised mineralisation was removed during the mining early this century, however the mine has continued to be famous as the source of the largest crystals of gypsum recorded from anywhere in Australia. Selenite prisms up to 30 centimetres in diameter and up to ten metres in length were found crisscrossing huge crystal lined cavities in the secondary ore zone early this century. Even more amazing was the plentiful occurrence of native copper in small arborescent clusters. These were often enclosed within the great prisms of transparent glassy gypsum, and so preserved in bright untarnished condition. Corbould, who was most interested in mineralogy, comments on these and other wonderfully crystallised oxidised copper minerals that he saw in the unusually cavernous ore material.
Mount Elliott is remarkable among Australian copper mines as an exceptionally lime-rich contact metamorphic orebody, which has produced superb crystallisation of the minerals of both the primary and oxidised zones. It is to be regretted that so little from the oxidised ore zone was preserved, with the exception of the huge gypsum crystals, which are represented in most major Australian museums.
If only one could travel back in time - to collect specimens or visit places in hindsight! The following extracts, taken from separate publications, give you some idea of the mineral riches that previously existed. They both concern the same locality - the "Garibaldi Gold Mine" or "Garibaldi Crystal Mine" as it is also sometimes known. The mine was situated near to the now deserted gold-mining towns of Solferino and Lionsville. This site is not far from the present day town of Tabulam, in North-Eastern NSW.
Rich alluvial diggings gave way to deep mining on the field, as the miners followed the gold- bearing reefs underground. In c.1912, when diggers were trying to sink a shaft to cut the Garibaldi reef, the ground sounded hollow when struck with their picks. It was decided to put in a shot of explosives. When the dust had cleared, they saw that they had broken into a fairyland - a crystal cave lined with calcite crystal. Tourists came from as far as Grafton to gaze on this spectacle. It must have still been a sight years later, in the early 1920's, when George Smith, Inspector of Mines for NSW wrote this report for the NSW Department of Mines:
"A very interesting occurrence of this mineral (calcite) may be seen in a large vugh in the Garibaldi Mine (Lionsville). It was interesected obliquely at one end by a tunnel... As exposed, its largest dimensions are 70 ft. by 16 ft. and 9 ft. high. It is lined with crystals of calcite of all sizes up to 2 ft. or more in diameter, some are cloudy, but most are transparent of light sherry colour, or colourless, and fine examples may be obtained of the variety which shows double refraction clearly and is known as Iceland Spar. Further exploration might show that the cavern extends beyond its known limits, but nothing has been done to enlarge it, and it remains as when first discovered. Though many of the crystals have been broken and removed, there yet remain so many intact that the damage is hardly noticeable...... Liquid inclusions from small to large bubbles as much as 2 inches long were seen containing possibly a desert-spoon full of the liquid..... upon some of the large crystals, short stout, hexagonal prisms of secondary calcite have been deposited. As single crystals and groups they are attached to the polished surfaces of the large crystals, and a very slight jar will detach them from their smooth base."
It was not to be for long, as a passage from the book Forgotten Country - The story of the Upper Clarence Gold Fields, by Isabel Wilkinson records.
"There arrived in Lionsville c. 1924, a German, Dr. Stroebal, and soon a new sensation stirred the district. The crystal was to be sent to Germany for the manufacture of "high quality lenses". Machinery was brought and set up to extract the crystal and a case mill, powered by an early model Fordson tractor to cut timber for packing the precious glass-like blocks.... Many of the locals had jobs in the new industry - taking out the blocks of crystal; cutting timber for the mill, making the cases for packing; carting the finished crates of crystal to Grafton for loading on to boats......Dr Stroebal gave instructions... none were to be broken, and as each piece came out, a crate must be tailored to fit it.....It has been said that Dr Stroebal travelled to Grafton each time a consignment went out and personally saw it shippedsafely away to Germany...."
What a shame! Imagine the tourist drawcard that such a place would make today! It is ironic that this "Iceland Spar" calcite was probably sought for rangefinder devices that eventually were to be used as weapons of war in the coming decade.
Bibliography:
A Contribution to the Mineralogy of New South Wales, George Smith*
Mineral Resources Publication No. 34, 1926 pp 96
Forgotten Country, Isabel Wilkinson 1980, ISBN 0 9593763 0 5, pp 227
*This same gentlemen is the grandfather of long-time Society member Sir Howard Smith - collecting must run in the family! Howard supplied this photograph of a cleavage fragment from the mine - 7cm x 7cm
If you ever get your hands on any of Queensland’s Geological Survey publications that date back to the turn of the century and beyond, many make for very interesting reading. If you look at any of the present day equivalents, they don’t have the same appeal. Today’s publications mostly resemble a scientific text book, full of (to the layman) unintelligible tables, borelogs and text. They are written for an audience of mostly highly educated professionals in the big mining arena.
80-100 years ago things were quite different. The audience then also included battlers, gougers, tributers, prospectors and would-be diggers. Many of them were uneducated, using their brawn to swing a pick and pay their way. They humped their swags from rush to rush, chased rich surface lodes, or tramped overland in search of a quick pound or two. They needed their guide books written in a language that they could easily understand. The guides were also a tool of the Government, used to open up new territory to prospectors. If they could entice enough fossickers out into the bush, they may just have struck another Gympie or Charters Towers to enrich the state coffers.
The authors of these publications also in many cases tackled more than just the geology of the areas concerned. Some were explorers, geographers, anthropologists and mineralogists all wrapped into one. Their commentary comes out as a personal record of their observations and as a help to a fellow traveller and fossicker. It is hard to imagine the lot of the authors (and fossickers) of last century. They did not have the luxury of four-wheel drives, refrigeration and bitumen roads when they went out prospecting. On foot or horse-back, over dry inhospitable perhaps unknown country, with few maps, carrying all their provisions, their prospecting trips could last for months on end.
With this in mind here are a couple of excerpts from reports written last century. The first is by Robert L. Jack, Government Geologist for Queensland in 1895 who is credited with discovering the Great Artesian Basin (and with it our huge inland water supply).
"On making inquiries as to water between Cloncurry and Winton, I learned that the country was about at its worst, there having been no rain for nine months except in very local showers. The usual route up the Gilliatt River and Mackinley Creek to Beaudesert, and thence to Belkate, on the Diamantina, was practically closed for the season.... We had camped on the night of 20th December on the Gilliatt River, where it is crossed by the Hughenden Road. The waterhole had fallen to a puddle about 10 feet in diameter, and when we arrived we found it in possession of a large mob of cattle. After the water had been boiled twice and skimmed and decanted it was good enough to make tea with. The horses however, could not be expected to like it, and on the 21st five of them were missing."
This, on what is now is a major highway route only 100 years later!
Sydney Skertchly, the Queensland Assistant Government Geologist in 1897, wrote a report titled "On the Geology of the Country round Stanthorpe and Warwick, South Queensland". Again the writers style is of a diary, full of anecdotes, and his impressions of the surrounding countryside. On explaining why one portion of his notes are quite light on, he remarks:
"I would have fain seen more of it; but I had only brought two days rations and we had horrible weather, fog and rain, and though we stayed a day after we had eaten our last bit of food, and the river wouldn’t give up its fish, we were obliged to return to Ballendean, as the rain showed no sign of abating. My horse drowned himself in a waterhole, one of our men had to be sent back ill, and altogether it was geology under difficulties."
But these times did have their compensations - like being the first collectors to tread a gully. Skertchly continues with commentary about Spring Creek and its tributaries -
"The gravel is full of rounded pebbles of rock crystal, often as smoky quartz or cairngorm, showing freely the gathering of the carbonaceous colouring matter at the pyramidal end...Crystals but slightly abraded are by no means rare, some of large size. I found one (cairngorm) 4 inches in diameter and 9 inches in length. Clear transparent and colourless and beautiful pale blue topazes are common, the largest found by me being about an inch broad - it is broken across the basal cleavage. Sapphires, opaque, blue and green are fairly abundant, and small zircons, spinels and garnets also occur plentifully, diamonds are scattered sporadically, and are seldom larger than one-tenth of a carat, and finally gold occurs in many places, but in small quantities."
Later, he has a few home truths to say about topaz :
"I can seriously recommend this stone to those who cherish gems for their beauty and not their mere costliness. Unfortunately ladies only seem to know certain names, and so long as a stone is called diamond, a ruby, a sapphire, an emerald ..... a colourless topaz would cost less than a hundreth part of the price of a diamond, and would be even less costly than the paste, which though beautiful, is not a gem, and it would be real."
Little has changed in the past 100 years! The Department of Minerals and Energy has a reference library open to the public on the 5th Floor of 61 Mary Street, Brisbane, where these and many other publications can be viewed.
Bibliography:
R.L.Jack, Queensland Geological Survey Bulletin No. 1
1895,
"Artesian Water in the Western Interior of Queensland"
S.B.J. Skertchly, Publication No. 120
"On the Geology of the Country round Stanthorpe and Warwick,
South Queensland."
This gold, silver and copper mine in Far North Queensland has in recent time produced, and is still producing, mineral specimens of a size and quality seldom exceeded. Crystallisations of near perfection, combinations of species and colour contrasts,afford specimens beautiful enough to delight even the most fastidious collectors.
Notable among the varieties are colourless, sometimes doubly-terminated. scalenahedral calcite crystals up to 4 or 5 centimetres seated upon dark, doubly-terminated, glassy crystals of siderite, both singly and in groups.
The Red Dome
Opencut in 1995
Native copper occurs in nuggets, but crystals of bright copper have not been seen by this writer except for unusual specimens of bright native copper protruding from massive cuprite. In a reverse of this habit, small cuprite crystals are found investing ‘stalactites’ of crystalline native copper.
Manganese minerals occur as a powder covering siderite crystals, and in botryroidal bunches (psilomelane?). This latter form, when seated in vughs among bright green, crystallised malachite,makes for specimens of exceptional beauty. The same manganese mineral occurs associated with, and as inclusions in, clear calcite crystals to 4 or 5 centimetres, another quite dramatic combination.
Stunning specimens of crystallised malachite in globules overlain by perfectly clear and lustrous drusy quartz; and botryoidal, bright green malachite accompanied by stout, glassy azurite crystals up to 2 centimetres, are as desirable as any specimens from this remarkable deposit yet seen.
Minerals Reported from the Red Dome Mine, Chillagoe, Queensland:
- Sulphides
Bornite, Molybdenite, Pyrrhotite, Chalcopyrite, Argentite, Chalcocite, Pyrite, Stibnite, Sphalerite, Galena, Arsenopyrite- Oxides
Hematite, Magnetite, Quartz, ‘Limonite’, Cassiterite- Fluorides
Fluorite- Tungstate
Scheelite- Silicates
Grossularite, Andradite, Chrysocolla, Wollastonite, Epidote, Vesuvianite, Diopside, Hedenbergite, Orthorclase, Sericite, Tremolite- Tellurides
Sylvanite, Altaite, Petzite, Hessite- Carbonates
Siderite, Azurite, Calcite, Malachite- Titano-Silicates
Titanite (Sphene)- Sulpho-Salts
Wittichenite- Native Metals
Gold, Copper, Silver
(to December 1994)
After Robert L. Jack, the most influential person in Queensland mineralogy was probably Benjamin Dunstan. Working for the Geological Survey of Queensland since before the turn of the century, Dunstan rose to head the Survey for over two decades. He is credited with publishing many important reports, with a keen eye for the unusual and a genuine love of minerals. He was also a fine draftsman, and his illustrations contained in the reports are particularly detailed.
His major work the ‘Queensland Mineral Index’ published in 1913, is still a standard text today, and is not likely to be matched, listing over 18,000 entries of mineral occurences around the state. Here are two illustrated excerpts from reports written in 1904 and 1905, obtained from the the Department of Minerals and Energy Library.
Dee River Nugget
Last century much debate occurred amongst the mining fraternity
on the origin of gold nuggets. Were they deposited and built up
to a lump from the fine grounds of gold in the streams, did they
precipitate from solutions or did they merely erode from larger
gold specimens and were waterworn?
Benjamin Dunstan seemed to have
an answer when a large nugget was discovered in the Dee River not
far from Mount Morgan near Rockhampton in Central Queensland.
"...the evidence on this point showed conclusively that the gold had formed in association with quartz. The 85½ oz. nugget, on examination besides showing a frosted surface, was found to be penetrated by a number of six-sided holes. On closer inspection, after the specimen was cleaned, these holes proved to be the casts of quartz crystals, in which all the well known peculiarities of crystallisation of that mineral were reproduced, showing undoubtedly the gold to have been deposited in a vugh or cavity containing a cluster of quartz crystals. The following rough sketch will show how the gold occurred, and from it the conclusion will be drawn that the size and shape of the gold nuggets were very different when enclosed in the cavity of quartz crystals from what they were when found in the alluvial wash, after being worn into their present form by attrition".
From the
Geological Survey of Queensland Publication
No. 190, Records No. 1, By B. Dunstan
(Acting Government Geologist) 1904
Calcite
Crystals with Pyrites Inclusions, at Golden Gate, Croydon
"In the block shaft being sunk at Roger’s Extended Mine, on the Golden Gate line of reef at Croydon, a quartz reef has changed into calcite, in the cavities of which calcite crystals have been formed.
"Figure 2, Plate 5, shows the general appearance of the
crystals as they appear in groups, with the lines of pyrites
inclusions passing through them. Figure 1, on the same plate,
illustrates the character of the twinning, the pyrites dust
inclusions on the terminal faces, and the median line of
microscopic crystals of pyrites traversing the group of calcite
crystals at right angles with the principal axis".
Gypsum Twin Crystals at
Eukalunda, near Bowen
"Specimens of Gypsum penetration-twin crystals have been received by the Geological Survey Office, Brisbane, from Eukalunda, near the Durham Mine, where they are stated to occur in a formation in granite close to sedimentary rocks".
From Geological Survey of
Queensland Publication
No. 196, Records No. 2, By B. Dunstan
(Acting Government Geologist) 1905
Many collectors starting out ask this question wanting a simple answer. It’s easy, you might think. You just ‘know’ a good specimen when you see one don’t you? Trying to express in words what makes a good specimen is more difficult. It really depends upon your point of view, and your ultimate goals as a collector. We all at some time or other return from a fossicking trip with our prized finds which we then spend hours cleaning and trimming to bring out their best features. Because we have found these specimens ourselves, they also immediately take on a special significance to us as collectors. We are willing to dismiss many of the specimens shortcomings in allowance of the fact that they are ‘ours’, and we rightly elevate them in rank in our collections!
Mineral judges at shows such as the Gemboree just past, are governed by a rigid set of rules that endeavour to allow specimens to be judged impartially, regardless of value or rarity. So what makes for an excellent specimen when factored for competition purposes, may perhaps appear insignificant, even ordinary to many collectors. Points are awarded for labelling, proper identification and crystal perfection etc, but the fact remains that a nice clean quartz crystal that could be purchased for $5.00, may conceivably beat a proustite crystal valued at $500.00 that has a damaged prism face. I know which I would prefer in my collection! But from a mineral judges point of view, the quartz was a better specimen i.e. it fit the judging criteria to a better degree.
So discounting the ‘I found it factor’, and the rigid set of mineral judging rules, what do we look for? Price is a good indicator, and with dealers having to be competitive to survive commercially, you will find that some specimens are dearer than others for a specific reason. This could be: size, rarity of type, colour, perfection of crystallisation, lack of damage, famous or rare location, and also ‘aesthetic appeal’. A good rule of thumb is the more specimens that you look at, the better you will become at identifing those that stand out from the pack. As I said, price on a dealers stand is a good indicator, but it is not always so. For instance, many times you will come across a dealer selling a flat of same type specimens, all of similar size and all priced exactly the same. This is probably because the dealer bought them at a bulk price, and although knowing them to vary in quality, is willing to sell them at a set price just to recoup his outlay plus profit with no extra work required pricing them seperately.
This, then, is where you get to exercise your ‘aesthetic’ choice, and take into account those other points mentioned. Lets say you have chosen the specimen type that you wish to add to your collection, and there are number to choose from. Don’t immediately choose the biggest - big is not always best in minerals! Carefully look the specimen over for damage, chipped terminations especially can devalue a crystal specimen. Check that the specimen is not glued or repaired (or in fact fraudulently constructed, as has been the case with some amethyst and calcite geodes and cassiterite specimens seen lately). Are the crystals of unusual habit or exhibit features such as twinning or inclusions? Is the colour, lustre or transparency of one specimen better than others? Are the crystals seperate, or are still attached to the host matrix, as these are usually more desirable. Finally look at the actual arrangement of the crystals on their matrix. Are they just a lump, or do they create a striking visual effect.
The best specimens tend to have a matrix that provides a good base for display, as a backdrop to show off the crystals. The matrix may provide contrast in colour, but it should not constitute a disproportionate amount of the specimen, and it helps if it is able to ‘sit’ and display in a cabinet without props or aids. Look at photos or view ‘classic’ specimens on display in museums - they all tend to have a central focal point to the viewer. This is usually a single crystal or crystals that are larger than their surrounding ones. A spray of crystals with one or two large ones on a druse or carpet of crystal, is preferable to a mass of all similarly sized crystals.
So there it is! After a while you will not need to consciously think of these factors, but you will soon find yourself becoming more discerning in your choice of specimens. You may look back at your own collection and think to yourself, why did I buy this or that? This shows that you are learning, and becoming a more knowledgable collector.
John Sampson White, former curator of the Smithsonian Institution’s mineral collection, recently described how fancy, aesthetic crystal groups of the competitive exhibit kind no longer appealed to him, and he added that you can learn more about mineralogy from one loose quartz crystal than you can from the biggest and flashiest quartz group the world has ever seen.
This assertion might be open to debate, but the point he made was that the interest and instruction in a mineral specimen lies not only in its aesthetic qualities. Well, we all say Hear, heart, to that, and we would also agree with him that one of the many great pleasures of mineral collecting is found in handling, examining and studying a specimen, for one never knows what one might find.
Once on a very dull and overcast day, I purchased a specimen which was displayed in a dark corner. It was labelled Tear-drop smithsonite, Broken Hill, NSW. and I bought it purely on this information, for it was impossible to really see what I was getting, except that the tear drop crystals were apparently fairly small. At home the next day, I unpacked the specimen and examined it closely in daylight.
The tear-drops turned out to be myriads of 5mm quartz crystals which had grown upon and among lustrous black crystals of sphalerite. Almost colourless single and stacked rhombs of calcite were distributed over the specimen, some upon, others totally enclosing pink crystals of rhodochrosite.
Further examination under a hand-lens disclosed a small plate of pyrite which was studded with tiny cubes of pyrite, the whole embedded among a forest of quartz crystals. A sparkling nest of fine, hair-like jamesonite next appeared under the lens, followed by a few tiny rhombs of rhodochrosite perching on the tips of quartz crystals, and finally inclusions of jamesonite in calcite crystals.
The back of the specimen was a repeat of the front, except that the calcite crystals were larger and darker, the partial inclusions of rhodochrosite more visible within the calcite crystals, while a pocket of quartz crystals thickly investing half the specimen left the other half free to be covered in matted jamesonite. Furthermore, the number 13783 on the back identified the specimen as having once been in the possession of a noted Sydney collector.
The specimen has no matrix; it is all crystallised minerals which by their placement demonstrate that the first to form was sphalerite, then came the quartz followed by rhodochrosite, then the jamesonite and pyrite with calcite last of all.
Far from originating in Broken Hill, the specimen was from the classic Romanian locality, Baja Sprie, and although pretty to look upon, it is certainly replete with interest when examined, and laden with information when studied. Under a microscope there might still await discoveries, left or right-handed quartz crystals perhaps, or different crystal forms of calcite.
John Sampson White might have exaggerated somewhat, but he was certainly in the right direction. Because for solace, relaxation, as a learning exercise or just to fill in time, there are few substitutes for handling one’s mineral specimens one by one and examining, studying and contemplating them.
Throughout past ages and until quite recent times, mineral collectors increased the variety in species and locality of their collections by exchanging specimens with other collectors in places remote from their own. After 1841, when the famous Penny Black ushered in postal systems as we know them throughout the world today, contacting distant collectors and arranging exchanges became easier, and therefore more popular and frequent.
Before the Lapidary Club of New South Wales was formed in 1953, there were no mineral and gem shows in Australia, no gemkhanas or gemborees. There were no dealers to spread arrays of rare and beautiful specimens from world-wide localities before our eyes, no world travellers on our doorsteps with car-loads of crystals, that we might pick and choose additions to our collections according to our finances and our fancies. We could only send mail orders to perhaps Ward’s Natural Science Establishment in the United States, or to Gregory, Bottley & Company, (no Lloyd then) in Britain, calculate exchange rates and hope for the best. The alternative was to exchange specimens through the mail.
It was not until March 1955 that our first mineral magazine, ‘The Australian Amateur Mineralogist’, appeared on the scene. Six months later it carried its first mineral dealer’s advertisement, that of Specimen Minerals (Australia) Limited, offering Broken Hill cerussite in fine crystallised specimens, reticulated, arrowhead etc., 2 inch by 3 inch 35/- ($3.50), or Broken Hill anglesite in lustrous orthorhombic crystals on crystallised cerussite, 2 inch by 3 inch, 42/6 ($4.25). Purchasing from Specimen Minerals, however, was still a mail order operation.
Before even this service was available in Australia my only methods of collecting minerals were by personal field collecting, which brought meagre results when transport was by push- bike, and by exchange through the mail, usually in response to classified advertisements in the United States magazine ‘Rocks and Minerals’. In 1956 I published an article in this magazine and soon received over 100 letters offering exchanges as a result of it. It seemed that American collectors still relied upon mail exchanges too.
All of these letter-writers were answered in laborious longhand, but I chose only two with whom to arrange exchanges and these remained constant swappers of specimens for the next ten years. Others became exchangers on a periodic or once-only basis, but the associated correspondence itself was fascinating. It told of collecting trips in exotic places and of events in families far away. Of course, the curiosity and excitement aroused by the arrival of a surprise box of specimens constitute emotions for which one never loses the profound desire and unlimited capacity to enjoy. Whether from Italy, Britain, Czechoslovakia or the United States, never in all the years did an exchange fall below expectations.
My two constant American exchangers of minerals both died in 1967. By then gem and mineral shows were becoming common annual events, mineralogical societies were soon to be formed and the need for mail exchanges of specimens waned. My last article in ‘Rocks and Minerals’ was published in 1987 and produced not even one letter offering exchanges. The golden years of mineral exchanges by post had become a happy memory.
Over eleven years of exchanging specimens by mail, never was a letter unanswered, a parcel of specimens unacknowledged nor a courtesy overlooked. Furthermore, the specimens received as exchanges always seemed to be at least the quality of those sent, and most often were superior or greater in number.
The advent of our own magazine, ‘The Australian Journal of Mineralogy’ with its welcome section of classified advertisements, has raised possibilities of again enjoying the delights of mineral exchanges with other collectors, Australian as well as foreign. Although but two issues are so far in print, the Journal has already carried several advertisements for the purchase, donation or exchange of mineral specimens, and our own Newsletter, a year or so ago, carried overseas addresses of collectors wishing to exchange specimens. With fond memories of earlier years when fascinating correspondence of humour and goodwill, along with mysterious parcels bearing foreign postage stamps, arrived regularly in my letterbox, I have taken up the advertised invitations on several occasions.
After a year I still await a reply to one of my letters. I have had no acknowledgement, let alone thanks, for a parcel I sent gratis and with no strings attached. To two letters in response to advertisements I have had no reply. What a difference from the unfailing good manners of the collectors of the 50’s and 60’s!
Corresponding and exchanging with collectors around the world carries with it a heavy responsibility to one’s country, quite apart from the pleasures this activity brings. We can all be judged by the courtesy, generosity and good manners, or the lack of them, exhibited by just one of our countrymen or countrywomen. Our own Society Members would never offend in any way, but it is unfortunate and true that bad manners are indeed sometimes displayed by Australians interested in minerals.
How easy it is, therefore, to give one’s country a good name or a bad one. Recently I answered an advertisement for an exchange of mineral specimens with an overseas address and received a marvellous reply from a Scotsman who not only sent a list of available minerals and their interesting localities, but also regaled me with the wonderful benefits to be derived in a snow storm from a dram or two of single malt whisky. Who could fail to love the Scots after that? My parcel is on its way to him, no strings attached.
As the hobby of mineral collecting entered a new Golden Age from the 1950’s, so too, perhaps, the exchange of specimens through the post is about to enjoy its renaissance. Such practice is truly an engrossing facet of mineral collecting and opens the door to the acquisition of unusual collector-collected specimens from remote or poorly known localities rarely found in dealers’ stocks. Moreover, the rules are simple: return of exchanges guaranteed if not satisfied, full stop.
The implied, unwritten and seldom mentioned rules, however, are equally important. Answer letters, acknowledge parcels, exercise courtesy. In other words, display good manners.
It is evident that there is some confusion amongst amateur mineralogists about the naming of minerals. It doesn’t matter whether it is for competition purposes, for the labels of one’s own collection or just plain knowledge, the incorrect naming of minerals indicates a lack of desire to do the most basic things correctly. Just like any other hobby, why bother if you are not prepared to take that little extra time to do things properly.
Where to look for correct names is very simple as there is only one definitive reference text for all mineralogists and that is: Glossary of Mineral Species 1995 by Michael Fleischer and Joseph A. Mandarino. This A5 sized book costs around A$25 and can be purchased from The Mineralogical Record in the USA or through mineral dealers.
Collectors and mineral enthusiasts quite often confuse the mineral species name with either the group or variety names. As this article is extremely abridged by necessity, here are some examples.
- Quartz var. Amethyst - Almandine (instead of Garnet) - Schorl (instead of Tourmaline) - Orthoclase var. Adularia. - Gypsum (instead of Selenite) - Elbaite ( instead of rubellite ) - Andradite var. Topazolite
If you are not sure what your mineral’s correct name is, then either look it up in Fleischer or ask someone who does know. I find it hard to believe that a person who claims to be interested in minerals as a hobby, has not enough enthusiasm to make the effort to get the name right.
The definition of a mineral has changed recently. The International Mineralogical Association has accepted the definition by Nicklin (1995): In general terms, a mineral is an element or chemical compound that is normally crystalline and which has been formed as a result of geological processes. There are some exceptions like mercury which occurs naturally as a liquid at normal temperatures, but the new definition will now accept extraterrestial substances as minerals, whilst previously recognised species from Laurium in Greece will now be discredited because they are formed from the weathering of slag.
To do this topic justice would take a much larger article than this. But amateur mineralogists, please make the effort to be correct in the most basic area of your hobby, the name for your mineral.
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