Category: StreetSmartNaturalist

Tuscon Gem/Mineral: Tents of Trilobites

If ammonites rule in Tucson, then trilobites run a close second. Again, you can buy them by the bag, as jewelry, in slabs, on plates, and even one at a time. At the lowest end, you spend as little as a two bucks, for the hundreds and hundreds of less-than-an-inch-long trilobites from Morocco. For big spenders, there are the one-of-kind crustaceans that will cost several thousand dollars, including a pea-sized one for $700. And, of course, nearly every seller is willing to make you a special deal.
A seven foot wide panel
As usual you get what you pay for, noted one high end dealer, who disdained the cheap trilobites from Morocco. Some of these spectacular trilobites seem almost too perfect to be real. The specimens have heavy ornamentation with spines and tails so fragile that they look as if they would break if you touch them. And in many cases they did break. The guy preparing the fossil simply collected them and glued them back in place, or he may also have made a new appendage with resin.

Did these two really die together?

Some of my favorites are where various species are cemented together to make it look like all lived in harmony. If you are interested, there are several good web sites on how to detect fakes. A nice, non-commercial one is from trilobites.com. But if you don’t care and just want a nice looking trilobite Tucson is the place to come.


Mom and the kids?

Tucson Gem/Mineral: Acres of Ammonites

Judging from the fossils that I have seen at the Tucson Gem and Mineral show, ammonites once ruled the world. I have only seen one small section of the displays but ammonites are by far the most abundant group of fossils, numbering in the thousands. You can buy them individually, by the bag, and by the the pound. They range in size from less than an inch to four feet in diameter.

A gaggle of ammonites

They come from places as diverse as Morocco, Russia, Columbia, and Madagascar. Most are whole. Some are split in two, revealing mineralized chambers. Many have been polished. Others are pyritzed. At one display, in a hotel room, the ammonites have been mounted elaborately with wee ones glued to bigger ones and split with whole. I also saw one massive ammonite-choked chunk of rock from Morocco that had been drilled out to create a wine rack.


A rafter nifty specimen from Canada


I was lucky to see the massive four foot diameter specimens. They had sold to an undisclosed buyer from Austin, Texas. He had paid $9,000 in cash for two of the giants, both of which had been cut in half. According to the guys getting ready to box and ship the ammonites, one was going to the buyer’s home and one to a museum.

A boy and a very, very big ammonite

My only disappointment was in how little information was listed with the fossils. A handful had the scientific name, age, and locality, but most had nothing but price. Still the show of ammonites is impressive.

A table of ammonites from Madagascar