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Meteorite Times Magazine Contents Paul Harris

Featured Articles Accretion Desk by Martin Horejsi Jim’s Fragments by Jim Tobin Bob’s Findings by Robert Verish Micro Visions by John Kashuba Norm’s Tektite Teasers by Norm Lehrman IMCA Insights by The IMCA Team Meteorite of the Month by Editor Tektite of the Month by Editor

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Meteorite Times Magazine Wilder, Idaho: A Professional Grade Meteorite Martin Horejsi

Wilder is a handf ul f or both the hand and the eye. But f inding beauty in Wilder takes some skill and experience. But nothing is required to appreciate the rare bit of geography it was f ound in. I’ve heard that the state of Idaho, if f lattened, would be one of the largest continental states in the US. But of course it’s not. Instead Idaho is the lef t over af ter the surrounding states grabbed their territory. Essentially it’s an east-west state f illed with north-south mountain ranges. Of ten it is easer to travel through a bordering state on your way to another point within Idaho, whether Montana, Oregon, or Washington. Idaho is home to f ive known meteorites of which 40% are stones but none of them f alls. The two non-iron meteorites were f ound about 150 miles by car f rom each other Although Idaho is a f airly large state, most of the f latter f armland where stone meteorites are most conspicuous is f ound in the southern region with leanings towards the west. So two stones a two-hour drive apart does not mean they have to be related. Even if they are the only two in the state. Wilder is a stone meteorite f ound in 1982. initially a f ellow named Alan Noe discovered a 1.970 kg piece of unusual rock in an unplowed f ield about 8 km north of the town of Wilder. Eight years later a second much larger piece of Wilder was f ound about 1.4 km f urther north of the f irst specimen. This second piece weighed in at 26.6 kg.


Wilder is an H5 chondrite with some shiny metal, but not near as much as it had when it f ell long ago. The city of Wilder “surrounded by vast agricultural lands growing a diverse variety of crops which include potatoes, sugar beets, onions, corn, grain, and mint. This area is unique in one crop, as it is known f or growing “hops” which are used in the brewing of beer. “ At least according to their website. Any place that specializes in a beer-related commerce must be a good place, right? Seems not much else happens in Wilder given their state website has has a 2006 copyright date. As an H5 chondrite, Wilder joins the ranks of the earth’s most popular meteorite type. And f urther, as a weathered chondrite, the most amazing thing about Wilder f rom a collection perspective, is that its f rom the US state of Idaho. Wilder has a rusty exterior that surrounds a darker chondrule-f illed matrix sprinkled with plenty of small metal f lake. The visual appeal of this stone is more f or the prof essional collector. To most, it is a dark brown matrix with darker brown or lighter brown chondrules, and the occasional grey one.


The inch-thick slice in my collection has a richly oxidized exterior classic of meteorites who f ell decades to centuries bef ore being f ound. The climate in southwest Idaho would certainly rust-up a meteorite f aster than dryer, hotter regions like Kansas, Nebraska, and Oklahoma. The triangular complete slice in my collection is a handf ul at ~1kg. There is no published weathering number f or Wilder, but the lack of any rimming indicates, in my mind anyway, that this stone is a W2-3-A using both designations as noted on of all things, the Wikipedia Meteorite Weathering page.


The “Prof essional Grade” nickname I have f or Wilder is because its f eatures are subtile. I’ve shown this slice to hundreds if not thousands of people, and very f ew ever spot any f eature on their own, and just barely register interest in the highlights I point out. There is still plenty of shiny metal in Wilder. However, Wilder is also a f airly porous meteorite dense with conspicuous but small holes throughout the matrix. In f act, there are so many holes that under magnif ication Wilder looks f ibrous.


Age cannot hide wrinkles. The classic thumb printing is obvious on a slice this thick. It will take many more centuries to rust-out the hidden beauty hiding under the dirty coat on this once homeless stone. Also f rom a collecting standpoint, the Wilder Meteorite is an excellent place holder f or most collections given that it is a rarely available sample f rom the Gem State of Idaho. Yes, I do count myself lucky to have a very nice specimen of Wilder in my collection. But when next to my main mass of the Jerome, Idaho meteorite, Wilder is yet another great sample of a geographically rare stone only temporally preserved with me. But Jerome is a more personal story. Until next time‌.


Meteorite Times Magazine Collecting My Thoughts James Tobin

The end of one year and the beginning of the next always seem to be a time of ref lection f or me. I think about the things I did during the year and the things that I did not complete. This last year I lef t two ceramics projects I wanted to do not even attempted. So they roll over to 2016. I was thinking just days ago about the up coming Gem Show in Tucson and I realized that I had actually only bought two meteorites last year during the whole remaining 10 months af ter the 2015 gem show. I wondered about what that meant. There were several possibilities. First, I have too many meteorites already and that it takes something really special to now get beyond my buyer’s resistance. A trait I have f rom my upbringing in an outrageously f rugal home. Second, might be that I was too busy with everything else in lif e to do much shopping f or meteorites. Thirdly, it might be that there have been so many f antastic meteorites brought to the market in the last couple decades that I am actually satisf ied with my collection as it is. I am not sure that any one of those reasons explains why I did not get new collection pieces f or 10 months. It may be a combination of all three. But, the Tucson Gem and Mineral Show is coming soon. I always get excited about going and seeing my f riends and the meteorites. I am sure that I will f ind some great space rocks again. Guess I should order some more Rikers now so I have them f or when I get home f rom the show. Beginnings of years is when I think about management of the meteorites and the collection and that’s what this article is going to be mostly about. Everyone displays and stores their meteorites dif f erently and here are a f ew things I have done. We have all acquired many small pieces of meteorite along with our more sizable space rocks. I have tried to be a little creative with how to store and display these smalls. Many f it in membrane boxes and I have plenty of those. Some meteorites just don’t work f or membrane boxes or deserve something better. And since I have a liking f or stuf f that is old I have placed many meteorites into bottles with cork stoppers and handwritten labels on the outside. It is a quaint and attractive way to protect and display them. I make wooden stands that hold a dozen or more bottles. They look nice in the display case; take up little room and theref ore make a f ew more meteorites accessible. Sometimes I put into a bottle crumbs that develop when cutting or f lakes that come of f when cleaning. Even dust sometimes if the meteorite is special enough to warrant the extra trouble of collecting the dust f rom the saw. The bottle holder shown below has some of those type things along with some small meteorites.


I started years ago making caliper mounts f or some of the larger whole individual meteorites. I have this love like I mentioned above f or old or old-looking stuf f . So the idea of getting beautif ul new polished brass caliper stands was just not in my thinking. I go instead to the garage and get some steel rod and bend it and braze on steel nuts and a steel post threaded on the end. Then take some brass threaded rod and cut some pieces an inch or so long. Af ter drilling a dimple in one end and cutting slot f or a screw driver in the other the threaded rod is used to adjust and tighten against the meteorite. Then I put a circle cutter into the drill press and make some round wooden bases to screw my steel posts to. They are easy to make and look old and f it my DIY mentality.


I have been a antique clock restorer and repairer f or most of my lif e and when I see an old glass clock dome I always try to buy it. These have made their way into my meteorite collection as well. They of ten come with a wooden base. The clock itself is of ten missing or beyond repair so I have the base and dome and into them goes a meteorite. This works well f or the ones that need to stay a little dry too. Once they are covered with the glass dome they are in a micro environment that does not change. Just a little concealed desiccant and the meteorite is Ok f or a long time. Another little trick I have been using lately is


to take the humidity indicator cards that I have a lot of and use my hole punching tools to cut out just the indicator spots and dispose of the rest of the card. This saves a lot of room, leaves the meteorite more visible and still lets me monitor the dryness of the container.

I have two or three meteorite spheres and I made stands f or them out of clay with meteorite powder added to it and f ired them with glaze colored with meteorite powder. There is nothing particularly artistic about the stands. They just serve a utilitarian purpose. But I like to merge my hobbies whenever possible.


I have always used the plastic bags with the white patch f or writing on. I am sure these are commonly used by many of us. I originally had some conf idence that they were sealed and my meteorites were protected. What I have learned more recently by including a humidity indicator card in the bags is that they do not protect them and that within a f ew months a large amount of silica gel will be totally depleted. When I checked a container that had about a dozen bags of various meteorites I f ound every indicator card was above 50% relative humidity. The humidity monitors in my of f ice and my display cases usually show around 45 -50% so clearly the desiccant in the plastic bags was totally depleted and the meteorites not protected as well as I thought.


The plastic bags are not as big an issue really as the last paragraph might suggest. I use silica gel in bead f orm routinely with many of my meteorites. Since most are not going to show any problems regardless of the humidity, it is just going to be the occasional f ussy one that might suf f er. But it was quite an eye opener to see how f ast the moisture got into the bags. So I have to do some better monitoring and f igure out where the moisture is getting in. My guess at present is the zip lock strip. When I checked two of the strips, each were able to be squeezed tighter. So either I did not press them together tight enough originally or they relaxed with time and handling becoming less than airtight. My easiest solution f or the meteorites that I will not be getting into very of ten is to redo the bags with f resh desiccant and then place all the bags as a group into another container which is completely air tight. So that is one of my projects f or the beginning of this year. I still have a f ew meteorites on my want list. And I will keep my eyes peeled f or them at Tucson. But, regardless of whether or not I see those meteorites I am sure I will f ind some that I can not resist taking home. I have done a poor job of keeping up with the recent f alls. In f act a couple I could have gone and hunted I did not even hear about. I have been doing too much astrophotography I am a little disconnected f rom breaking meteorite news. But it has never been a big deal f or me to get every new one that f alls. I know it is the singular f ocus of some collectors. And paying the price of newly f allen stones is really a problem with my upbringing. I understand the dynamics of it. The high cost to go and f ind them, the dangers and recently the relatively small amounts of recovered material. And the f inders need to of course make money. I am not criticizing the hunter/dealers and their prices. I am just saying I am handicapped by a mental state coming out of my childhood which causes me to over think every purchase in lif e. So I guess it is good that I have never looked at my collection as an investment. I guess it is likewise good that I have never f elt that I had to have the largest most expensive and impressive meteorites. I have done well though and I have a f ine collection af ter f orty odd years of accumulation. And I think I have moved over some kind of a hump in my thinking. I am actually quite satisf ied with the state of the collection. I don’t think I am as obsessed as I was 15-20 years ago or even 5 to 10 years ago about acquiring more. Just getting a f ew each year is enough now. I was getting dozens each year back in the past. I love to look through the boxes of unclassif ied meteorites at the Tucson Gem Show. I always f ind a f ew meteorites that need a home and over the years many of these have made it into one display case. But a


f ew have f ound a sof t place to rest in small wooded instrument boxes. I f ound a batch of these at the local electronics swap meet. I don’t know what was originally in them my guess would be some piece of microwave equipment or a gauge. I have them in several dif f erent sizes and shapes. I cleaned them up and made black velvet pads f or the tops and bottoms. They are not air tight but work f or many of the nice f usion crusted chondrites.

Working and playing with the meteorites as described in this article has actually been way more f un then the acquiring of them was. There is the photography, the cutting and polishing and occasional thin sectioning of them, the microscopy of them; I enjoy those things all year long. I guess I am still obsessed with meteorites. As I sit here writing this I am literally surrounded by meteorites. Not a day goes by that I am not somehow involved with them. They have certainly provided a great amount of enjoyment and knowledge throughout my lif e. I hope that this upcoming year is an opportunity f or all the readers to also enjoy the meteorites in their collections and to those who are beginning collections, you have a great adventure ahead of you.


Meteorite Times Magazine Unclassified USA Meteorites from Coyote Dry Lake Robert Verish

A newsletter for “orphaned” meteorites from the USA. Featured this month is Coyote Dry Lake (circa 1995-2004)

This volume of my Bulletin of unclassif ied U.S. meteorites f eatures a new f ormat f or documenting these “orphaned” f inds. Hopef ully this will be a more convenient f ormat f or when there are more than 100 f inds to be reported. It is also conveniently coincidental with this being the 20th anniversary of the f irst reported Coyote Dry Lake meteorite being f ound (late 1995). I f ind it hard to believe that it has already been 20 years since I made that f irst f ind. It is also the 10 year anniversary f or the f irst time that Coyote Dry Lake meteorites appeared in a publication. I’ve appended my abstract to that paper at the end of this article f or the reader’s convenience. Strangely, there hasn’t been anything published since then, so maybe this is a good opportunity to remind researchers about this unique meteorite locality. But this article is not going to be an “update” on recent recoveries. That will have to be a f ollow-up bulletin to this article. This article will be more like a historical perspective of the f irst 10 years of this locality, f ocusing on the period of time f rom 1995 to 2004. Even though that period of time has already been recorded and documented, whatever data and inf ormation that can be retrieved at this present time only pertains to those f ew Coyote Dry Lake f inds that were selected f or classif ication. And although provisional numbers were assigned by the NomCom to all of the other unclassif ied f inds, it has recently been brought to my attention that the recovery data that was submitted f or over 250 f inds can no longer be f ound in the Meteoritical Bulletin Database. Back then, there was no on-line database and provisional numbers did not appear in print. Over the years and during the transition to an on-line database, this block of data became missing. But it wasn’t lost to history, because f ortunately, I still held onto this data. So, I’m taking this opportunity to make this data available, again, by publishing it on-line here in this bulletin.


The f ollowing “Bulletin” is just one example of an alternative way in which to document unclassif ied meteorites f rom the USA. It is my hope that this compilation will bring attention to the problem of the large number of unclassif ied meteorites f ound here in the USA, that are going undocumented. Hopef ully, some volunteers will of f er to help establish an on-line database that will document these “orphans”. Newsletter for Orphaned Meteorites from USA – Volume 2 No. 1 — January 2016 Meteorite-Recovery Inf ormation Table of Known (as of year 2004) Meteorite Specimens Recovered f rom Coyote Dry Lake: Specimens – f rom 1995 to 2004 – CyDL 001 thru CyDL 243

This “Bulletin” is just one example of a way in which to record U.S. OC meteorite f inds. Hopef ully, this compilation will bring attention to the problem of the increasingly large number of meteorites f ound here in the USA, not only going unclassif ied, but even going unreported. Hopef ully, some volunteers will of f er to help establish a similar database that will document these “orphans”. In the meanwhile, I will do my part and continue to gather data, and along with others, make a list of known meteorites, that otherwise, would eventually become “f orgotten meteorites”. References: “Making Tracks Across the Southwest: The 2006 Desert Symposium” Abstracts f rom the 2006 Desert Symposium – Robert E. Reynolds, compiler Calif ornia State University, Desert Studies Consortium and LSA Associates, Inc. April 2006 Abstract: Coyote Dry Lake Meteorites: what can Holocene meteorite falls tell us about the recent drainage history of the Coyote basin? by Robert S. Verish The Coyote Dry Lake meteorites are named af ter the Calif ornia dry lake on which they were f ound, a large playa 20 miles NE of Barstow in San Bernardino County. For the past 10 years, over 250 chondritic stone f ragments and individuals (meteorites) have been f ound at this locality. Every known f ind has been documented. Each of them has had its date-of -f ind, weight in grams, and GPS coordinates recorded. This inf ormation was reported to the Nomenclature Committee of the Meteoritical Society. Having supplied all of the required inf ormation, it was now possible to get provisional numbers assigned to each of the more than 250 f inds. The f irst known f ind f rom this locality was made by this author in 1995, but it wasn’t classif ied until 1999. It was characterized as being “H5 S2 W3”, as are the majority of the f inds f rom this locality. But, over the years as f inds were continually made, each would be closely scrutinized, and every specimen that was deemed “out of character” (f rom the original H5 S2 W3 stones) would be turned in f or classif ication. Presently, there are nearly 50 of these specimens that have been classif ied. Although a proper pairing study has yet to be done, here is the breakdown of the current classif ications: Number of classified finds (stones) 21

Classification(UCLA)

Pairing determination

H5 S2

10

H4

(most are "probably paired") (1 group of whole individuals are "probably paired" and at least 2 other groups of "possibly paired" stones)


5

H6

2

H5-6 S2 breccia

1 1 2

H5-6 S4 breccia H3 L5-6 S2-3 W1

2

L6 S4 W5

1

LL6

paired" stones) (1 group of whole, fresh stones are "probably paired" and another group of weathered stones are "possibly paired") ("probably paired") (unpaired) ("probably paired") ("probably paired")

The recovery inf ormation f or each of these classif ied stones were tabulated, and this table was submitted to the Nomenclature Committee. The name “Coyote Dry Lake” was approved by the Committee f or these classif ied stones, as well as f or the remaining 200 “provisionally numbered” f inds. The name “Coyote Dry Lake” appeared f or the f irst time in print when the Meteoritical Bulletin #89 (2005) was published in the “Supplement” to the Meteoritics & Planetary Science – Journal of the Meteoritical Society (Volume 40). Based upon the pairing scheme in the above table, it can be reasoned that there have been at least 10 separate events, called “meteorite f alls”, which have occurred over time. It is this phrase “over time” that is now at the center of the discussion about Coyote Dry Lake meteorites. Over HOW MUCH time is the question. For if it can be shown that these various meteorites accumulated over geologic time, and that their recovery was f ortuitous due to recent exhumation by accelerated def lation/erosion of this lakebed, then 10 separate f all events is not an unusually high number. But, the consensus among geomorphologists is that Recent drainage of these Mojave Desert basins has been relatively static. Coyote Dry Lake meteorites have garnered attention recently, albeit f or the large number of meteorites f ound upon the lakebed (more than 250 stony f ragments and individuals), yet, if the number of separate f all events can NOT be shown to have occurred over geologic time, and are accepted as having occurred recently, this will be of great interest to those researchers studying the rate of inf lux f or meteorite(s) (f alling) upon this planet. Reconciling the number of Coyote Dry Lake meteorite f alls with the Recent drainage history of the Coyote Basin is an endeavor that will require more in depth study by various, cross-disciplined researchers in order to resolve. It is to this end that the f inding of the Coyote Dry Lake meteorites are being presented to this workshop. Presentations f rom a workshop held in April 2005 at the Desert Studies Center in Zzyzx, Calif ornia, are now published. Key issues addressed in the workshop included the f ollowing: (1) “Correlating patterns with current interpretations of drainage history based on the physical record and seeking explanations f or major discrepancies.” (2) “The meeting encouraged geologists and biologists to interact to develop a broader perspective on the types of research that are being conducted to address issues of regional drainage history. The convenors hope that these new opportunities of interaction among scientists of dif f erent disciplines will lead to f uture proposals f or collaborative studies.” In keeping with the above perspectives, this abstract endeavors to promote a more in depth study of the Recent drainage history of the Coyote Basin and to petition f ellow researchers at this workshop to assist in this “cross-disciplined” study. Bibliography: Russell, S., et al, 2005. The Meteoritical Bulletin, No. 89, in Planetary Science 40, No. 9, Supplement, A201-A263. Meek, N., 1994., : San Bernardino County Museum Association Quarterly, 41(3), p. 5-13. Clarke, M.L., 1996. Infra-red stimulated luminescence dating of sands from the Cronese Basins, Mojave Desert, Geomorphology 17, 199-205. Previous Bob’s Bulletins:


Bob’s Bulletin – Vol. 1 No. 1 — In my f irst Bulletin, I introduced the phrase “orphaned-meteorites f rom the USA”. I def ined these “orphans” as being un-witnessed-f all Ordinary Chondrite (OC) meteorite “f inds” that are recovered in the U.S. Unf ortunately, the vast majority of U.S. f inds are of this type. I went on to write that these U.S. f inds were being orphaned f rom the f amily of “approved” meteorites f or the f ollowing reasons: 1) The lack of f unding f or U.S. researchers to authenticate, classif y, and document/record these U.S. OC f inds has resulted in several new [negative]; trends. 2) The increasing trend of commercializing the classif ying of meteorites by U.S. researchers has priced U.S. OC f inds out of the market, and 3) The increasing trend of U.S. researchers to turn away OC f inds, even when f inders of U.S. OC meteorites are willing to pay f or their classif ication. Bob’s Bulletin – Vol. 1 No. 2 — In my 2nd Bulletin, I went into more detail about why I use the phrase “orphaned-meteorites f rom the USA”. I f ocused on the lack of U.S.-tax-dollar-f unding and why no f unding was going towards the classif ication of these particular meteorites. In hindsight, I now realize that I should have pointed-out that there is also a lack of f unding f or just authenticating and recording that a U.S. meteorite has been f ound. This f unction should never be conf used with “classif ying” a meteorite, which is obviously way more labor intensive and costly. Bob’s Bulletin – Vol. 1 No. 3 — In my 3rd Bulletin, I proposed the idea of an on-line database f or these “orphaned” and other unclassif ied U.S. meteorites. This would have to be an all-volunteer ef f ort, much in the same manner that the American Meteor Society has established the Fireball Reporting System. This database would give f inders a central point to report their f inds and have a f ield ID number issued to them. This “Field ID” would ref lect which US state and date of f ind. The f unction of this database should not be conf used with already established processes of getting a meteorite “classif ied”, which is obviously way more labor intensive and costly. Bob’s Bulletin – Vol. 1 No. 4 — In my 4th Bulletin, I reported that several U.S. researchers were volunteering their time and ef f ort to record and publish meteorite f alls and f inds, such as, Creston and Misf its Flat. I suggested that this method of cataloging newly f ound US meteorite specimens could be expanded, but the main hindrance is that there is no f unding f or this kind of ef f ort. Meteoritical Bulletin: the search results f or all provisional meteorites f ound in “USA” – Published by Meteoritical Society – Meteoritical Bulletin, Database. Meteorites of Calif ornia the list of f ormally-recognized Calif ornia meteorite f alls and f inds. My previous Bob’s Findings articles can be found *HERE* If you would like to sponsor any of these orphans, and help in the f unding f or getting them classif ied, in order to get them entered into the Meteoritical Bulletin Database, then please contact me by email:

bolidechaser at yahoo-dot-com


Meteorite Times Magazine Souslovo L4 John Kashuba

Souslovo Timeline: 1966 – Fireball 1997 – Hay cart wheel chock 2002 – L4, S2,W0/1

Large and small barred olivine chondrules in Souslovo L4. Cross-polarized light (XPL).


Large broken barred olivine chondrule. Souslovo L4, XPL.


Metal and troilite grain in and around silicates. Troilite (FeS) is bronze color. Field of view is 3mm wide. Souslovo L4, incident light.


Same view as above in both incident light and cross-polarized light. Souslovo L4.


Same view as above in cross-polarized light. Souslovo L4.


Metal grain contrasting with surrounding silicates. Souslovo L4, XPL.


Metal and silicates. Souslovo L4, XPL.


Metal grain with silicates. Field of view is 3mm wide. Souslovo L4, XPL.


Close-up of above metal grain and silicates. Field of view is 0.5mm wide. Souslovo L4, XPL.


Layered chondrule. Souslovo L4, XPL.


Complex chondrule. Souslovo L4, XPL.


Norm’s Tektite Teasers: Libyan Desert Glass Ventifacts. By Norm Lehrman (www.TektiteSource.com) There is as yet no clear consensus regarding the detailed origins of Libyan Desert Glass. What we do know is that 28.5 million years ago in what is now Egypt’s Western Desert, in the southern part of the country near the Libyan border, there was a significant encounter with a cosmic visitor. No crater is yet confirmed, but it is believed that the land surface may have been over a thousand feet higher at that time. Libyan Desert Glass is a melt of nearly pure quartz grains that fused and flowed during some immensely hot thermal event. We know it involved a bolide that contained chondritic material because the dark browngray streaks and patches in some LDG have been shown to carry elemental signatures matching stony meteorites. This was dust from the demolished impactor that mixed into the viscous molten sand. Debate mostly centers on the nature of the event. Was it a direct crater-forming meteorite impact? Or was it a comet? Or a thermal airburst like Tunguska, maybe with no crater at all? Whatever the case, most scholars agree that 28.5 million years ago there was a massive burst of thermal energy associated with a body from space that exploded in or above the surface of the earth in this area. The ground surface, which evidently consisted of very pure quartz sand with only traces of other weathering resistant minerals, fused to a considerable depth---at least a foot or more---into a straw yellow glass. Microscopic images show that every quartz grain collapsed into a long spindle shape, forming a mosaic of parallel eyes set in a braided matrix of viscously flow-banded ribbons. Tiny bubbles were stretched into elliptical planar shapes, sometimes yielding a silky chatoyance to the glass when viewed from certain angles. None of the glass has ever been found that shows definite flight-modifications as is characteristic of tektites and many impactites. It was a fused ground-surface crust of molten glass that slumped and flowed short distances. It is found in a very large area, over 80 miles N-S and 30 miles E-W, but a central ring-shaped zone about 3 miles in diameter is reported to carry the highest concentrations, possibly reflecting the location of ground zero. If it is true that the original ground surface was a thousand feet higher at the moment of the event, then we are forced to suppose that as the underlying bedrock gradually eroded away, the LDG crust fragmented and deflated to its


present location. Such processes would inevitably have dispersed the glass widely, so its present regional distribution does not demand any extraordinary sort of event. There is a further story to the LDG jewels we now behold in wonder. The place where they are found is a region of linear sand dunes and wind-deflated desert pavement corridors. Constantly pelted (truly “sand-blasted”) with wind-driven sand grains, exposed parts of each piece have been fluted, shaped, and polished. Such stones are termed “ventifacts”, and each facet reveals a common direction for the prevailing winds. The frosted base that most specimens exhibit is the part that was buried and protected from erosion in the desert pavement. The occurrence of LDG was mentioned as early as 1850 but the first significant investigations were not until the 1930s. This is a very remote and challenging setting hundreds of miles across the sand sea from the nearest roads. Even with today’s equipment, carrying sufficient fuel and water for the arduous trip is a challenge, entailing significant dangers. The nearby borders with Libya and Sudan add a measure of political/military risk. I have been told that it has been a recent requirement of the Egyptian government that expeditions finance a military escort. Our best specimen ever, a wonderfully sculpted and polished 168 gram iceberg of jelly-like clarity was recovered over 10 years ago during an expedition by Parisian mineral and meteorite dealer, Alain Carion. There have been a number of recent expeditions, mainly by Russian meteorite dealers, and there is at least one commercial photographic tour group that offers tours into the area. There have been recurring reports that the Egyptian government no longer allows LDG to be taken out of the country. But this story of challenge and danger and overwhelming odds sets the stage for one of the greatest pieces of LDG trivia: The straw-yellow scarab in the center of King Tut’s pectoral is LDG! Somehow, someone gathered LDG in early Egyptian times, the days of the Pharaohs! Your mental pictures should involve camel caravans in the deepest desert. But then, perhaps we shouldn’t be surprised. In the collecting area, Paleolithic artifacts are widespread, mainly consisting of simple blades of the sort that were set in rows into slotted sticks to form sickles for some of the earliest grain farmers, ancestors to a great many of the people now on earth. These artifacts tell a different story concerning this region: this land was


not always a raging desert. In the long experience of the Desert Glass, rivers and lakes and tropical jungles passed over the land. It seems there was a time when fields of grain were growing there, and people were learning agriculture. But those days came to an end, and now the desert holds a firm grip.

Libyan Desert Glass posesses the highest silica content of any natural glass known. The fluted and polished forms often have a beautiful sculptural quality. The color, as seen by the human eye, varies with the spectral character of sunlight at various seasons and latitudes. In near equatorial regions, pieces take on a glow of neon-apple-green, while at higher and lower latitudes, the glass is typically perceived as pale straw-yellow. As natural works of art, LDG certainly ranks with the most beautiful of stones.


Meteorite Times Magazine Seymchan Meteorite – 355.9 Gram Transitional Part-Slice Paul Harris

Our Meteorite of the Month is kindly provided by Tucson Meteorites who hosts The Meteorite Picture of the Day.

Contributed by Geof f Notkin/Aerolite Meteorites, IMCA 4242 – Copyright Aerolite Meteorites. Geof f writes: I am quite attached to this intriguing part slice, which was the test cut f rom the large Seymchan mass I acquired, directly f rom the f inders, and described as “the f inest transitional pallasite ever recovered.” One slice sold at auction in NYC f or $45,000. Etched, and packed with dark olivine crystals, it is a moody beauty. Submit Pictures to Meteorite Pictures of the Day


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Once a few decades ago this opening was a framed window in the wall of H. H. Nininger's Home and Museum building. From this window he must have many times pondered the mysteries of Meteor Crater seen in the distance. Photo by Š 2010 James Tobin

Meteorite Times Magazine  

January 2016 Issue

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