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Page 1: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that
Page 2: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Meteorite Times MagazineContentsby Editor

Featured Articles

Accretion Desk by Martin HorejsiJim’s Fragments by Jim TobinMeteorite Market Trends by Michael BloodBob’s Findings by Robert VerishMicro Visions by John KashubaNorm’s Tektite Teasers by Norm LehrmanMr. Monning’s Collection by Anne BlackIMCA Insights by The IMCA TeamMeteorite of the Month by EditorTektite of the Month by Editor

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Page 3: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Meteorite Times MagazineAvanhandava, Brazil: A No-Nonsense H4By Mart in Horejsi

Avanhandava is a stone not usually represented in private collect ions, andeven more rarely in anything larger than a gram or two. The dist ribut ion ofAvanhandava is very low even though there are over nine kilograms incirculat ion.

Avanhandava fell in San Paulo, Brazil in 1952. It is listed as an H4, S2, anddespite it ’s mundaneness, Avanhandava has found it s way into a handful ofresearch studies.

Page 4: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

There are much bet ter looking chondrites then Avanhandava. In fact , moststones, even those pulled f rom the hot sands are more enjoyable to gaze at .Avanhandava as represented in most collect ions is lit t le more than a f riablerust -t inted blob with occasional dist inct chondrites.

Init ial reports stated that the mass of Avanhandava that arrived on earth was30cm in diameter. However, it broke up and 9.3kg were preserved. Accordingto the Catalogue of Meteorites, of those few kilos, the largest pieces are7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Sincethat totals 12.42kg, but the f irst two weights exact ly total the listed TKW, Iassume that some subdividing has occurred within the limited sub 10kg init ialreport .

Page 5: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Avanhandava is certainly not a looker, but it does represent a half -century oldwitnessed fall. And any witnessed fall is a good fall in my book.

Unt il next t ime….

Page 6: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Meteorite Times MagazineMy New Meteorite SawBy James Tobin

I have had a great adventure the last couple weeks. My old diamond saw that Imade about 30 years ago f inal died and I needed a new one. There is nothingon the market to go out and buy that will do what I want f rom a diamond saw.So I took a week or so to think about the design and made a few sketches ofideas and then spent the last week making the saw. Of course this was thelast two weeks of March.

Paul said, “You have to take a lot of pictures for an art icle unless you arekeeping the design a secret .” Well, there is no reason to keep it secret . Thereis nothing really new that was not in the other saw it is just a lot bet ter. Thirt yyears ago I had to make a saw fast . I used a lot of welding on parts and usedreally scrap stuf f f rom the garage to put the old saw together. Not this t ime.

This is an image of the nearly f inished saw. I is just lacking it s splash covers.

I had the t ime to do this right and make it the way I wanted so I did no welding.

Page 7: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

No brazing either it is made f rom aluminum and a few hard wood spacers. Theonly plast ics are the splash covers of clear acrylic and the motor and pulleycover and blade cover made of black ABS.

First let me say that I made nearly every part except the actual machinescrews that hold it together. The aluminum plate and angle I had in the garagef rom taking apart some old pieces of print ing equipment . I had been holding onto this metal f rom years ago when I got out of the print ing business. Thewhole cost for this saw was under fort y dollars and that is because I had tobuy the pump for the coolant . I had two pumps but af ter sit t ing for 20 yearsneither worked.

I used the motor and pulley mechanism f rom the old saw since that part I hadwell engineered 30 years ago. But the broken belt that provoked this wholething forced me to modify the pulleys. They were a st range double groovevee belt t ype deal that I could not f ind a replacement for anywhere. So I tookthe pulleys and turned them down to get rid of the middle peak and makethem into a normal single vee design.

I had two thick aluminum plates that were the side f rames f rom a huge oldphoto t ypeset t ing machine. They were 1/4 inch thick and would make a greatsaw top st ructure. There was a hole in the middle of the plates and I decidedto ut ilize the hole for the coolant to drain of f the saw. I have become annoyedtoo many t imes by having to drain the saw af ter use and having to pull thesaw apart to change the blades. And then there are the t imes that the thinslice of meteorite slides right down into the coolant tank and I had to take thesaw apart to ret rieve the slice. So the plan for this saw was to spray coolantonto the blade and let it be completely exposed above the top of the sawst ructure; much like a commercial chop saw. I would have to recirculate thecoolant and I needed to keep big pieces of rock out of the tub that would beunder the saw. I did not want pieces of rock jamming up the pump. This will allbe pret t y easy to understand by looking at the at tached images.

Page 8: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

This is the top plate of the saw with the coolant containment wall at tached.

I had an old piece of elect ronic equipment that I had torn down but I had keptthe case f rom and it had six round vent ilat ion screens. I took those and madethem into f ilt er screens by placing them onto a plate of aluminum thatcovered the big drain hole in the saw top. So nothing big enough to clog mypump or coolant spray nozzle would make it to the tub that had therecirculat ing coolant . Also no slices or pieces of rock will ever fall anywherewith the new saw.

Page 9: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

This is an image of the six drain screens that prevent any rock part icles f romreturning with the coolant to the tank under the saw. The pump and spray nozzlework f ine with the saw created mud but would clog with larger part icles.

For years I have writ ten about how I at tach the meteorites to a mandrel withdop wax and make slice af ter slice by moving the mandrel over with a screwpushing mechanism. I am st ill using that system but this is much more ref ined.The new saw has much t ighter tolerances and the whole mandrel mot ionmechanism can be removed and replaced with a table cut t ing plat form forwhen slices are diced down to smaller size pieces.

Page 10: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Pictured here is the mandrel holder and lateral mot ion mechanism. The dialindicator allows me to cut slices that are exact ly the same thickness one af teranother without removing the rock f rom the saw.

I had used a rolled threaded rod of large diameter and coarse thread in theold saw. This t ime I machined the threaded rod for the mechanism thatadvances the stone into the blade. I used a small diameter shaf t and cut f inethreads into. It is much smoother and I have a lot more cont rol and none of theperiodic error that I had with the old rolled threaded rod. I would turn thehandle to advance the stone and it would not move for half a turn and then itwould advance the other half rotat ion. I have none of that with the machinedthreads I cut . The t rade of f for using a thin diameter rod however is that Ihave much less support in the whole carriage the moves forward and back. Soto avoid any sagging when cut t ing a heavy rock I have installed an “ant isagpin” f rom the bot tom of the carriage to the f rame of the mechanism below.The round end of the pin rides smoothly on the bot tom f rame rail and therecan be no sagging under load. The addit ion of an un-threaded rod parallel tothe threaded rod is another improvement . There can be no up and down ortwist ing mot ion of the carriage as it moves forward and back past the blade.

These are the parts for the cross mot ion carriage that move the meteorite in andout through the blade. The next image shows the mechanism assembled.

Page 11: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Since the whole blade was to be exposed above the saw top plate I decidedthat I could use an 8 inch blade as well as the 6 inch size I have been using. So Idesigned the blade cover so that it would have wide enough sides to coverthe last port ion of the 6 inch diameter blades and be thick enough to handlethe 8 inch blades with some room to spare. I drew up pat terns on cardboardand cut them out then t ransferred the contours to 1/8 inch thick ABS plast icand cut out the two sides. ABS plast ic has a textured side and a smooth sideso I had to turn the pat tern over for one of the sides so they would both havethe at t ract ive texture when glued up. I made an assembly jig with a board andf inishing nails to hole the plast ic sides down in alignment and let me wrap theband of plast ic around the edge for the top of the blade cover. I stackedblocks made of foam core the correct thickness in between the two sidepieces and glued the assembly together.

Page 12: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that
Page 13: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

These images show the blade cover cardboard templates and the cut parts, thenthe parts in the assembly jig drying af ter gluing.

I love working with ABS plast ic it cuts easy and breaks st raight if you score iton both side. And it glues together with solvent t ype glue so the pieces arewelded as if they were one piece when it drys. I made the motor and pulleycover the same basic way. Pat terns cut f rom cardboard and the pieces gluedusing my right angle picture f raming clamps and small hobby speed clamps.

I had thought about making a f iberglass tank to contain the coolant within themiddle of the saw. But decided to take aluminum angle and cut it and rivet itdown to the saw top plate and create a wall. I had been storing a big can ofassorted aircraf t rivet for 30 – 40 years and had used a few f rom t ime to t imebut this was my chance to make use of them. The hard aluminum alloy rivetswould give me a fantast ically st rong connect ion and would never rust . I alsosprayed the inside of the wall area with a plast ic sealer so the coolant couldnot leak.

I worked the project as sub-assemblies. I made the cross mot ion mechanismwith the carriage and support as an assembly of it s own. I had the motor andpulley and blade arbor mechanism as another assembly. I just needed tointegrate the various sub-assemblies into the f inished saw design. I alreadyhad the cross mot ion mechanisms and carriage made so I could mark the sawtop plate for where it would be located. Then I cut and folded the coolant wallaluminum angle to leave spots where components would later be mounted.

This picture shows the posit ioning of the sub-assemblies in the aluminum wall.

Having the ¼ inch thick top plate let me tap all the mount ing holes for thevarious items that needed to be mounted. I used most ly brass screws toavoid rust ing but could and may switch them out for stainless steel screws.

Page 14: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

But I don’t think there will be much galvanic act ivit y between the dissimilarmetals of aluminum and brass. Af ter all I am using dist illed water with a lit t lealcohol which is nearly elect rically neut ral for chemical act ion. And the sawshould drain to nearly dry quickly af ter use. But , I did not want to use steelscrews within the coolant tank area. I f igure I will need to take it apart f romt ime to t ime and do not want to fool around with corroded screws.

I had been annoyed with the old saw that it did not have nice knobs to turn formaking the mot ion of the stone laterally or into and out of the blade. So I hadsome scrap exot ic hardwood (the species I no longer remember, but it wasnice wood). I turned it into knobs and think I made nice at t ract ive contours thatwill make the saw nice to look at and pleasant to use. There is a knob thatlocks the aluminum mandrel holder into the cross mot ion mechanism. There isa knob that holds the mandrel in posit ion af ter it has been moved over for thenext cut . Two addit ional knobs were needed one for the end of the lateralmot ion adjustment screw and one on the crank of the forward and backwardmot ion threaded rod. It took a lot of t ime to turn the knobs but I am happy withthe way they look and work.

I was a lot more interested in the appearance of the saw this t ime. I wasconcerned that it worked well f irst of f , but I wanted something that was niceto see also. Over the last 15 years I have been asked to cut meteorites oncamera on two occasions and to be perfect ly honest I was not proud enoughof the saw I had to feel great when using it on camera. But , this saw I think ispret t y at t ract ive and well engineered.

The images will t ell you the rest of the story on the const ruct ion. So I will moveon the the next annoying part of the old saw I was going to t ry and removef rom this design. I have cut rocks long enough to expect that there will bespray everywhere. But , I am t ired of being soaking wet af ter a couple hours ofwork. So one of my goals with this saw was to make covers that would giveme visibilit y while st ill containing almost all the coolant .

Page 15: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

The splash guards can be seen in this image and they worked very well I get hit byno coolant now.

I was pret t y sure that I could heat acrylic plast ic and bent it using the heat gunI have for shrink insulat ion. So I made templates again out of cardboard forthe size and shape of my shields and then cut them af ter they were correctf rom 1/8 inch clear acrylic. I heated the plast ic with the heat gun then bent thest raight folds of two of the shields using wooden blocks to apply pressure andmake the bends. For the large shield that folds back out of the way on a hingeI heated the plast ic and used the same template I used for the curve of theblade cover, but with some alterat ions to give me a drip lip on the f ront edgeand a f lat vert ical port ion to raise it to the correct height . It needed to behigher than anything else near the stone so I had plenty of room. I wanted thef ront shield to just be a lit t le higher than the drip lip of the curved swing ableshield over the middle of the saw. You can see the f inished shields in thepictures. I made a shield for the lef t side of the saw just to keep the remainingspray that when in that direct ion but it needed no heat ing and bending.

The coolant needed to be squirted at the edge of the blade near where thestone was being cut . But I did not want a huge st ream. So I cut of f a length ofcopper tubing saved f rom an old ref rigerat ion unit that I had saved thecompressor out of . I needed a vacuum pump for high voltage raref ied gasilluminat ion experiments 20 years ago. I cleaned up the copper tubing andformed it into a curve that mimicked the contour of the blade cover because itwould be next to the blade cover when installed. I took a t iny tubular rivet f rom

Page 16: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

my clock making supplies and would use that as my nozzle for the coolantsprayer. It had an opening of only about 30 – 40 thousandths of an inch. Itwould nicely rest rict the amount of coolant dispensed and make a goodst ream. I drilled a t iny hole in the side of the copper tubing near the end which Ihad bent to cross over in f ront of the blade. I soldered the tubular clock rivetinto the hole and closed the copper tube with solder at the same t ime. Downat the other end of the copper tube I soldered a thick brass plate with twoholes to the side of the copper tube to mount the copper coolant supply tubeto the saw f rame. The tube now very solidly mounted just needed a piece ofplast ic aquarium tubing and a pump to make it work.

This is a closeup of the coolant spray nozzle. The way that it is at tached andaligned can be seen in the next photograph.

Page 17: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

There is lit t le else to describe. I needed to change the AC elect rical cord forthe saw motor. Af ter 30 years it was due for a change. I run the saw of f aVariac to cont rol the speed a lit t le bit and have used the switch on the Variac,so I just made a waterproof plast ic box on a plast ic stand for the cord tomotor wire connect ions.

So that is it , I got some 8 inch diamond blades that were st ill t hin and put oneon and made my f irst cuts. I picked one of the most f ractured pieces of AlHaggounia that I could f ind and mounted it on a mandrel. I made seven cutsone af ter the other moving right across the width of the stone. The sliceswere so smooth that they almost did not need to be lapped. It cut with solit t le st ress that the slices did not fall apart on the f ractures. I got rock mud allover the saw but proved it worked. I keep it clean and probably always willbecause this may be the big home engineering project of my lif e.

Page 18: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

This is an image of the saw ready to run with an 8 inch blade.

I hope some of the readers found this interest ing I know it was pret t y far f romthe normal discussion of meteorites and probably was pret t y dry stuf f . But ,maybe it gave some enthusiasts a few ideas for saws of their own.

Page 19: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

These are the f irst slices I cut on the saw. The meteorite is Al Haggounia and itwas full of f ractures. You can see how smooth the surface is they have not yetbeen lapped.

As a fun experiment I got to the very end of a stone and decided to see if Icould split the last remaining lit t le bit at tached to the mandrel. So here is ashot of that piece af ter cut t ing. The feeler gauge is .014 inches and the rockslices on each side are only about .028 inches. I lef t it slighted uncut so it wouldhold together for photos.

Page 20: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that
Page 21: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Meteorite-Times MagazineMeteorite Market Trendsby Michael Blood

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This Month’sMeteorite Market Trends

by Michael Blood

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Page 22: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Meteorite Times MagazineEl Mirage Dry Lake Clean-upBy Robert Verish

Volunteers needed to help “clean-up” El Mirage Dry Lake.

The t it le of this art icle may mislead you into thinking that I am looking forvolunteers to help clean up all the remaining meteorites f rom El Mirage DryLake (well, maybe I am).

Actually, this “clean-up” is really an event where a large group of volunteerscome out to El Mirage OHV Recreat ion Area (twice a year) to help the Friendsof El Mirage (and the BLM) with their clean-up and maintenance of the area.The 2014 “Spring Clean-up” was held on May 3rd. The “Fall Clean-up” will beheld on October 25th. And f rom what I have learned f rom past “Clean-ups”,this is a great opportunit y for public out reach (regarding meteorites), and topromote meteorite-recovery to a large group of people (while actually at adrylake).

Because of last years federal government shut -down, the October 2013clean-up was cancelled. That fact , and the forecast of very hightemperatures predicted for the Mojave Desert , resulted in a lower thanaverage turnout (85 volunteers) for this recent May 3rd “Spring Clean-up”.Past turnouts have had as many as 175 volunteers! That ’s a lot of people atone gathering all walking about on a drylake, bent over collect ing refuse,picking-up metal-debris with magnets, and leveling hummocks with rakes.

Page 23: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Ample opportunit y for someone to “accident ly” f ind a meteorite. It would onlybe prudent to have a “meteorite expert ” on hand to conduct public out reachand to help ident if y any possible meteorite f inds.

This was exact ly what I suggested to the Friends of El Mirage (thecoordinators of the “Spring Clean-up”), and much to my surprise I received aprompt reply f rom the Barstow BLM. Apparent ly, not only did the FoEM agreewith my suggest ion, but the BLM agreed, as well, and extended to me apersonal invitat ion to their next clean-up and to “set up an informat ion tableand even bring a few samples”.

Ever since a $15 fee per vehicle for ent ry onto El Mirage was established, Ihave had no luck in convincing my f riends to join me in a group meteorite-huntat this Dense Collect ion Area (DCA). But af ter I reported back to them aboutthis last Clean-up, and how volunteers get a f ree overnight pass, they are nowwant ing to join-in at the next Clean-up.So, if you would be interested in joining us in this out reach ef fort , but havesome quest ions about what volunteers do, here is an overview of the lastClean-up:

The day started of f at the Visitor Center with a breakfast at 7:00AM (a $3donat ion is suggested). Then regist rat ion started at 7:30, followed by theformat ion of work crews. By 8:00AM these crews had already headed out thedrylake area to begin work. Work crew projects included general clean-up andt rash collect ion, lakebed maintenance, Joshua T ree fence repair, and usingmagnets to remove nails and other sharp objects f rom the lakebed andcampsite areas.The work crews stayed out unt il around noon, returning to theVisitors Center for a BBQ lunch that was served at 12:30 and that wasfollowed by a raf f le drawing (the 50/50 drawing began at 1:00PM).

So, to recap, Pre-Registered Volunteers receive:a full breakfast ($3 donat ion suggested)a BBQ lunch (donat ion suggested)a f ree raf f le t icket (held at luncht ime)and f ree permit to overnight camping facilit ies.

This was a day of good company and good fun, and was a chance to giveback to one of the more popular public areas.

Page 24: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Breakfast starts at 7AM for clean-up crew volunteers.

On average more than 100 volunteers sign-up for the “Clean-up” which means

Page 25: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

it will be easy to meet people and make new f riends.

Volunteers f rom SCTA are eager to remove rocks and small sand-dunes f romthe racet rack port ion of the lake-bed. This mantenance crew knows where therock-pile is located.

Page 26: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Clean-up crew on their way back f rom a work “project ” site, returning to theVisitors Center for a much deserved complimentary lunch.

One of the CORVA volunteers display the magnets that are used for picking

Page 27: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

up “metal-debris”.

Here is an example of the kind of metal debris that is picked-up by the clean-up crew with their magnet -devices.

Unfortunately, no meteorites were recovered. Maybe someone will get luckyat the next Clean-up?

Page 28: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

EMDL 004 is classifed as “W0″ which means that it is unweathered! Essent ially,it is a f reshly fallen meteorite.

This means that relat ively lit t le t ime has t ranspired since this stone fell,

so, there’s lit t le chance that other stones f rom this fall having t raveled veryfar f rom where ever they landed.

They, too, are probably st ill sit t ing on the alluvium wait ing to be found. Maybestones even larger than 271g.

Had there been a witnessed f ireball event prior to f inding this “W0″ stone, thiswould be highly publicized.

Why there haven’t been dozens of meteorite-hunters clamoring about this“fall” & searching hard this area,

is a mystery to me.

Page 29: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Google Earth View : of El Mirage Dry Lake – San Bernardino County, CA –showing EMDL-DCA and meteorite f ind locat ions.

Aerial View : of a wet El Mirage Dry Lake – San Bernardino County, CA –showing many shorelines

Post Script: A spokesperson for the FoEM (Friends of El Mirage) wanted me

Page 30: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

to ment ion that , if you are unable to at tend one of the publicized Clean-ups,people who want to volunteer to clean up are always welcome at anyt ime ofthe year. Of course, you would miss-out on all of the socializing that comeswith a “Clean-up”, but you may st ill be able to negot iate a f ree overnight pass.If you do go, let us know if you f ind a meteorite. And Good Luck!

References:

Meteorites with Name = “El Mirage Dry Lake” f rom the Meteorit ical Bullet in: thesearch result s for all meteorites found on “El Mirage Dry Lake, California, USA”– Published in Meteorit ical Society – Meteorit ical Bullet in, Database.

El Mirage Dry Lake 004 f rom the Meteorit ical Bullet in: the ent ry for EMDL 004 –Published in Meteorit ical Society – Meteorit ical Bullet in, Database.

The Digital-Desert website for images and links about El Mirage Dry Lake.

Geology of El Mirage the original geologic history of the Antelope Valley.

Barstow BLM Of f ice the BLM website for the EMDL Of f -Highway VehicleRecreat ion Area : El Mirage Cooperat ive Management Area is now a Fee Area.

El Mirage Days the BLM website for the 2006 “Clean-up”.

Southern California T iming Associat ion the SCTA of f icial website.

CORVA the website for CA Of f -Road Vehicle Associat ion.

Friends of El Mirage their of f icial website.

El Mirage Dry Lake, California website for “Interest ing El Mirage Facts”.

My previous art icles can be found *HERE*

For for more information, please contact me by email: Bolide*chaser

Page 31: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Meteorite Times MagazineLayered Chondrules in Allende CV3John Kashuba

These photos were taken of four thin sect ions that were deaccessioned by aUS universit y. They appear to have been made by dif ferent people and atdif ferent t imes. On one, the cover slip cement has turned yellow. Some havelabeling engraved on the slide behind the sample. Some of this can beat t ributed to the sample size being very large, covering most of the slide.Some samples have been polished a bit thinner than the standard 0.03mm.This might have been intent ional since it helps reveal st ructures that areotherwise obscured by the f ine grained mat rix of this t ype 3 carbonaceouschondrite.

The layers in these chondrules dist inguish themselves by dif ferences intexture and composit ion. And these result f rom successive episodes ofaccret ion and heat ing. Layers tend to be f iner grained toward the outside ofchondrules. We see dif ferent t ypes of cores.

Core is a single crystal of olivine.

Page 32: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

This is the same view as the photo above. The polarizing f ilt ers have been rotatedput t ing the core grain into opt ical ext inct ion to highlight it s halo of f ine grained material.

Page 33: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Coarse core surrounded by f iner mineral grains.

Page 35: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

A barred olivine chondrule core with an unt idy f ine grained surround.

Page 36: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Two barred olivine chondrules and a layered chondrule.

Page 37: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Both chondrules have barred olivine chondrule cores. In the upper chondrule the bars areblue and red.

Page 38: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

A jumble of bars is at the center of the chondrule surrounded by medium size grainsand, toward the edge, layers of opaque material.

Page 39: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

The black circles and curved t races are metal. They show bet ter in the ref lected lightphoto below.

Page 40: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

The metal blebs and mineral grains in the center were surrounded by two metal shellsbefore the chondrule was sliced open for inspect ion.

Page 41: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

A 5mm diameter porphyrit ic pyroxene chondrule (with poikilit ic texture) is surrounded bydark and f inely crystalline layers.

Page 42: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Coarse center with f iner surrounding layers. Some mineral grains were plucked f rom thecenter of the chondrule during thin sect ion preparat ion.

Page 44: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

The outer layer is a barred chondrule so we know that part was fully molten at somet ime. When it solidif ied it s internal crystal lat t ice grew in alignment with the adjacentcore crystal.

Page 45: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Meteorite Times MagazineA Sweet Chlum Moldavite DumbellBy Norm Lehrman

Over the years, we’ve only handled a few moldavite dumbells and even thosewere not great . Recent ly we were of fered this gem by an Aust rian collector(and we accepted!) 5.4 grams, Chlum, Czech Republic.

A real beauty.

Page 46: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Meteorite Times MagazineHARRIMAN (of)Anne Black

The Harriman f ile is much bigger than the others with few pictures but manylet ters detailing a long, convoluted and dif f icult negot iat ion with many players.It was carried out by an associate of Oscar Monnig, who goes by the name ofVega or Bunch, not his real name according to Dr. Ehlmann, a resourcefulperson who not only did not use his real name, but even resorted to usingcoded messages.

The f irst document in the f ile is this index card dated Spring 1933, the f irstsign that a meteorite had been found in Tennessee.

All documentat ion is Property of the Monnig Collect ion – TCU

Not a very encouraging start , but Mr. Monnig was persistent , and when youwere looking for any kind of informat ion in the early 1930s, you wrote to thePostmaster! And that exact ly what he did in April 1935:

Page 47: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

All documentat ion is Property of the Monnig Collect ion – TCU

Not encouraging either, but things soon improved, and by June the existenceof the meteorite was conf irmed and “Bunch” was on it s t rail although he didn’tseem to part icularly like or t rust the people he was dealing with.

Page 48: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

All documentat ion is Property of the Monnig Collect ion – TCU

And then the whole thing turns into a shell game with the meteorite as thepea. Who actually has the meteorite? Mr. Davis in Harriman says it is Mr. Parksin Chat tanooga (locally called Ross Landing), or maybe E.L. Kenyon also inChat tanooga. Or maybe it is Dr. Cross, a pediat rician in Knoxville, or could it behis father, also a doctor. Some tell Mr. Monnig’s envoy, now signing Vega, thatthey have an of fer on the meteorite, others deny it ; either way “Vega” insistshis of fer remains $1 per pound, but only af ter he examines it . There seems tobe no t rust between anyone of those mult iple players. But ‘Vega’ is not givingup, as he explains to Oscar Monnig in a long and convoluted let ter.

Page 49: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

All documentat ion is Property of the Monnig Collect ion – TCU

Page 50: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

All documentat ion is Property of the Monnig Collect ion – TCU

By July Vega-Bunch is a bit more encouraging. He has heard f rom the DoctorsCross, father and son, who seem to know more than they init ially let on, theyadvise him to be pat ient . And now the pea, hmm… the meteorite, is said to bewith Mr. Parks. So while wait ing, Vega-Bunch writes poet ry, that he sends toMr. Monnig.

Page 51: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

All documentat ion is Property of the Monnig Collect ion – TCU

All documentat ion is Property of the Monnig Collect ion – TCU

By August the shell Game is heat ing up, and Vega-Bunch is resort ing tosending a coded message to Oscar Monnig. Yes, f inally, it seems that themeteorite has been located, but it does not mean that the holder of the peawill let it go. Oscar Monnig only wrote the t ranslat ion of the f irst line, anyonecare to t ry deciphering the rest?

Page 52: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

All documentat ion is Property of the Monnig Collect ion – TCU

The next day the news is discouraging: the doctors have located themeteorite, it is in Chat tanooga but they had to hire a lawyer to help recover it .What follows is Vega-Bunch long diat ribe about the legal system and localjudges in what he considers to be back woods. But again the doctors tell himto be pat ient , so he waits. And by October, he is st ill wait ing.

All documentat ion is Property of the Monnig Collect ion – TCU

All documentat ion is Property of the Monnig Collect ion – TCU

But by mid-October, he seems to be running of pat ience and goes toChat tanooga, where he gets informat ion on some of the shell-game players.He now knows that Mr. Kenyon has the pea (meteorite) but the problem isf inding Mr. Kenyon. He explains all that in a long let ter to Mr. Monnig.Communicat ions were indeed dif f icult in 1935!

Page 53: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

All documentat ion is Property of the Monnig Collect ion – TCU

In a follow up let ter, he gives a few more details and int roduces a new gameplayer, a Mr. Hembree the actual f inder of the meteorite, f inally. But he is nocloser to get t ing the meteorite as all those players are f ight ing betweenthemselves, threatening to sue each other and probably lying. This verypat ient man, so far, now feels like he “could eat nails”.

Page 54: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

All documentat ion is Property of the Monnig Collect ion – TCU

And then, only a week later, this telegram: The shell-game is over; somehowthe meteorite has been found and is on it s way to Texas and Mr. Monnig’sof f ice. Sorry, there is no explanat ion in the f ile as to how this happened soquickly.

Page 55: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

All documentat ion is Property of the Monnig Collect ion – TCU

And here it is f inally, the whole Harrison meteorite, in a picture stamped on theback by the Smithsonian Inst itute, but not dated.

But as it is quite obvious by now, Mr. Monnig was a very thorough andpersistent person, and he needed more informat ion. We don’t know when hewrote to Mr. Hembree, the last person to join the shell-game, but in August1950 he received this let ter f rom the f inder of the meteorite, who conf irmsthat yes, indeed, he is the f inder but seems to be just as baf f led as everyoneelse about the rest of the story.

Page 56: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

All documentat ion is Property of the Monnig Collect ion – TCU

Af ter all those t roubles and t ribulat ions, the Harriman meteorite is nowcomfortably set t led in the Monnig collect ion, it has been classif ied as a f ineOctahedrite, group IVA, with 7.96% nickel, and it has a beaut iful sharpWidmanstat ten pat tern.

Page 58: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

Meteorite Times MagazineMeteorite of the Month: GibeonPaul Harris

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

Gibeon Meteorite 1616 grams. 230 mm long – Copyright Jim St rope.Iron, IVA TKW 26 met ric tons. Fall not observed. Found 1836 in GreatNamaqualand, Namibia. The f ragments of the meteorite in the st rewn f ieldare dispersed over an ellipt ical area 275 km long and 100 km wide. Jim writes:When sit t ing in this posit ion it reminds me of a f ireball.

Submit Pictures to Meteorite Pictures of the Day

Page 59: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that
Page 60: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

catchafallingstar.com Nakhla Dog Meteorites

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Page 62: Meteorite Times Magazineto the Catalogue of Meteorites, of those few kilos, the largest pieces are 7.74kg in Colegio Estadual, 1.59kg in Avanhandava, 3.1kg in the USNM. Since that

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 © 2010 James Tobin