Snapshots from the Tucson 2000 Gem and Mineral Show
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Gone But Not Forgotten II

I found several contenders for my first ammonite when I visited with David and Roxanne Anderson of Earth's Past in Room 120 at the Ramada Inn. At right were matched halves a Phylloceras sp specimen from Madagascar, which has been sectioned through its symmetry plane and polished to reveal the colorfully mineralized chambers of its phragmocone. The beginning of its whorls is the ammonitella, which is the initial shell of hatchling ammonites. The nuclear ammonitella is surrounded in this specimen by a spiral of chambers of increasing size, and all but the final and largest chamber (body cavity) makes up the ammonite's phragmocone. This pair looked a bargain to me at $85, with a 25% discount to dealers with a resale license.

Shown above is another sub $100 contender for my ammonite shown by Earth's Past, one of these larger, paired sections of another Madagascar ammonite, an Orthosphinctes sp which had also been sectioned so that its colorfully mineralized interior chambers could be appreciated. These had presence and they were offered at $95 each less a 25% dealer's discount, take one or both. The pair worked out to $142.50 with the discount but I could have taken my choice of one or the other section for half of that. Deciding which would have been a difficult choice, as they had been perfectly split and were mirror images of each other. I thought it would be a shame to separate such a fine pair, so hopefully another collector with half again my budget will see these my way and take both of them home to be kept and appreciated together.

David and Roxanne hail from South Dakota about half of the year and their specialty is South Dakota fossils. They showed a number of South Dakota ammonites which had very attractive opalescent shells where the original mother of pearl shell has been preserved. The colors are created by light reflecting back through the nacreous shell surface after being diffracted by underlying layers of aragonite.

Above left is a 2.5 inch Hoploscaphite nodosus on matrix, from the Cretaceous Pierre Shale in South Dakota. The Pierre Shale originates from the Pierre Seaway, an epicontinental sea covering the western interior during the Campanian and Maastrichtian stages of the Late Cretaceous, from about 69 to 82 million years ago. This pretty specimen was marked a little over my budget at $125, but with the dealer's keystone discount of 25% it was 'legally' within reach...

Above right is another opalescent South Dakota ammonite on matrix, a Discoscaphite cheyennscesis from the Fox Hills Formation in the Pierre Shale which is noted for its pristinely preserved and colorful, opalescent ammonite specimens. This specimen was priced at $55 net.

Earth's Past [May-Sept Tel: 907.983.2880 PO Box 863, Skagway, AK 99840] [October-April Tel: 605.393.2878 3703 Dawn Street, Rapid City, SD 57703]

Now above left is one ugly mug! This specimen was shown by Fossil Lake Fish Company outside Room 151 at the Ramada It is the fossilized business end of a Xiphactinus audax, a giant fossil fish which was cleaning up the gene pools of lesser cohabitants of a Late Cretaceous seaway in North America during the age of dinosaurs. Believe it or not, with a head of 18 inches and a longest tooth of 2 inches, this one died while still a relative minnow... This was the largest bony fish that's ever lived, with the largest individuals pushing 20 feet in length.

These fish and the mosasaurs were at the top predators in those ancient oceans and they often devoured their prey whole. The fossil record testifies that their greed was sometimes fatal and has produced famous specimens of "fish within a fish". This Xiphactinus was recovered in western Kansas. I thought it was a pretty impressive piece for only $5000. Of course "only" is a relative thing, but I can tell you with certainty that if I were a Wall Street trader, this would have gone back East with me for my office wall.

Above right is a shot along one wall in their room, lined with large slabs of Fossil Lake fish, which occur in Wyoming's Green River Shales. These shales were laid down by the Green River Lake System covering western Wyoming, eastern Utah and northwestern Colorado during the Eocene period of the Cenozoic era about 55 million years ago. Fossil Lake, Lake Gosuite and Lake Uinta were the three lakes in this system. The prevailing climate then brought seasonal rains that washed a deposit of fine mud into the lakes each year, covering the bodies of dead fish on the lake bottom and preventing the normal process of decay. These shales have produced some of the most numerous and aesthetic fish fossils in the world. While paper thin, these shales accumulated to depths of 200 feet in some areas.

Most of these big pieces were in the four figure range, and many of them had already been sold when I took this picture. The large, bluegill shaped fish in the upper center of the picture is a Phareodus sp, which is a unique fish having spike-like fins below its body which it used to forage for food along the lake bottom. It was both a combination of scavenger and predator - all of the other species of Fossil Lake fish have been found in the stomachs of fossilized Phareodus, which reached a maximum length of about three feet.

Above from left to right are Fossil Lake Fish Company owners Bob and Bonnie Finney, and their friend Travis Rice, who was helping them mind the store at this year's show. These are some of the friendliest folks I've met at the Show and their smiles and enthusiasm are contagious. They are quick to invite others to come up and dig in their fossil beds in Wyoming and the story of me doing just that may become a future article at Bob's Rock Shop. As you can see, the Green River Shale they dig in produces some very handsome specimens, although I'm sure there's a lot of digging between the exceptional and rare ones.

Above right is a close up with detail of the paddlefish on the fossil behind Bob, Bonnie and Travis. It is a 30 inch Fossil Lake Crossopholis magnicaudatus, with a Mioplosus labracoides above and to the right of the paddlefish. This handsome upscale specimen was commanding $10,000.

Above left is a close-up of that large Heliobatis radianis ray piece in the wall shot above. The slab on that one is 28 inches by 54 inches and the ray is 8 inches in diameter and and 17 inches nose to tail tip. This piece also featured a number of aesthetically placed Knightia sp, which are present in the majority of the Fossil Lake specimens, and a Dyplomystus sp, out of view towards the bottom of the piece. This piece had already sold, going in the mid four figures. Knightia and Diplomystus are the most ubiquitous of the Fossil Lake fishes.

Above right is a rather fine individual Dyplomystus dentatus. This specimen's slab measures about 13 cm by 8.5 cm by 2 cm thick and the fish is about 8.5 cm long. Note the penny for scale. Fossils of these fish are relatively ubiquitous at the Tucson Show, but the vast majority are inferior and lack the delicate and fine detail preserved in this specimen. Click on it for a higher resolution view of the detail. This specimen jumped out at me from literally hundreds of other Dyplomystus specimens at the Fossil Lake Fish Company and I couldn't resist snagging it for a show report digital door prize. It cost me about 20 minutes of enjoyable searching and cherry picking through boxes of single Dyplo specimens and $12.

Fossil Lake Fish Company Tel: 307.877.9636 PO Box 92, Frontier, WY 83121

I encountered this rather bizarre and striking Lepidotes maximus reproduction displayed outside Room 162 by Maxilla and Mandible Ltd. My friend Jerry Ferrin provides some scale as he checks it out. This is of the largest and most complete of 3 known fossil examples of this species. It dates to the Jurassic period of the Mesozoic era. Check out this fish's rather unique dentition in the close-up above right. It must have dined on hard shelled food like mollusks and corals. For the decorator with a budget, at just $4000, it's an absolute must have as a companion piece to go with the Xiphactinus in front of Fossil Lake Fish Company...

Maxilla and Mandible Ltd. Tel: 212.724.6173 Fax: 212.721.1073 451 Columbus Avenue, New York, NY 10024

It wasn't all fossils at the Ramada Inn. Blaine Reed Meteorites was showing in Room 110, the same room where some Shows ago I purchased the first rock to coax $100 from my wallet, an aesthetically sculpted 216.5 gram meteorite found in 1966 on the Nullabor Plain in western Australia.

That's Blaine at left, showing off a mailbox which was struck by the witnessed fall of a 1455 gram chondrite near Claxton, Georgia around twilight on a December evening in 1984. Vietnam vet Don Richardson had just stepped out of his trailer when he heard a whistling noise that reminded him of an incoming mortar round, and then a loud bang as the meteorite struck his mailbox and knocked it to the ground. The chondrite, a type of stony meteorite containing millimeter to sub-millimeter spherical olivine and pyroxene bodies called chondrules, was recovered about 11 inches below the ground beneath the mailbox. The image at right is a photo I took of a small section of the Claxton, Georgia meteorite that was about thumbnail sized. The darker chondrules are readily discerned.

I asked Blaine if he had any particularly special pieces he wanted to show off and he suggested this 129.5 gram slice of Huckitta, above left, a stony iron pallasite found in Australia in 1924. Huckitta is the largest pallasite known, weighing over 1400 kilograms. What's so special about this slice is virtually all of Huckitta which has been available on the collector market has been extremely oxidized with weathering altering the original nickel iron matrix to hematite and magnetite. This pristine, unoxidized 9 cm slice wanted $15 per gram times 129.5 equals $1942.50 for a nice sized chunk of some of the rarest and most striking rock on Earth.

Above right is a tub full of irons from the fall which created the spectacular and world's best known impact crater, the Barringer Meteor Crater near Winslow, Arizona. Meteor Crater, now a national landmark, finally became the first impact crater on Earth generally recognized as such by the scientific community. It was known as Coon Bluff to early Arizona settlers and ranchers and assumed by the scientific community to be volcanic in origin. Daniel Barringer's turn of the century theories that it was created by a meteorite were scientific heresy until re-examined by Eugene Shoemaker in the late 1950s. Nowadays Barringer's insights and work are better appreciated, and it is known that Meteor Crater was created by the impact of an iron asteroid weighing several hundred thousand tons which approached at a relatively low angle and traveling at approximately 11 miles per second (40,000 miles per hour).

It disintegrated just prior to impact sometime around 50,000 years ago, with thousands of pieces breaking off the larger masses and scattering over the surrounding area. The explosion at the moment of impact is estimated to have been the equivalent of a 1.7 megaton bomb, creating an impact crater nearly a mile in diameter.

I couldn't resist one of these Meteor Crater irons, and the nicely thumb printed, 153.2 gram specimen depicted above left went home with me. Click on its still image to download and play a short (120 KB) MPEG movie I made of my new meteorite as I rotate it about in hand to show it off. At $45 I paid about 30 cents per gram for it, which I thought a pretty good deal for smaller, cherry picked specimen such as this.

I also purchased several other must have Meteor Crater related accouterments from Blaine to display with the meteorite - above right are the contents of a $7 gelatin capsule filled with metallic spheroids condensed from iron vapor that I've transferred to a glass vial for display. The vast majority of the impacting body creating Meteor Crater vaporized on impact, creating a cloud of super heated vapor which condensed as it cooled and rained these iron/nickel spheroids down upon the surrounding area. The large green sphere in the vial is a dried pea I included for scale.

At right is a 4 gram piece of Meteor Crater impactite which I purchased for $3. It's about 2.25 cm across. When a large meteorite strikes the Earth, part of the vaporizing meteorite fuses with rock melted by the impact, forming a terrestrial/extraterrestrial hybrid material called impactite resembling volcanic cinders. Impactites contain small grains of meteoritic metal when a cut surface is examined closely.

Space rocks register pretty high on my cool meter and I consider the $55 I left with with Blaine this year in exchange for these Meteor Crater specimens to be well spent. I plan to design and construct a special Meteor Crater combo display for them. Perfect companions for my Nullabor Plain octahedrite and Juancheng chondrite... :)

Blaine was also showing off a specimen of the priceless Kingsford carbonaceous chondrite, pictured in its special display case below. Be sure and check out the label describing the Kingsford.

Blaine Reed Meteorites Tel: 970.259.5326 907 County Road 207 #1, Durango, CO 81301

For another report on fossils at Tucson 2000, check out fossil collector and fellow Tucsonian Rik Hill's online report at Rik Hill's Scenes from the Tucson 2000 Fossil Show.

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