IMCA Insights – August 2006
Getting a Meteorite Classified
by Adam Hupé

What is involved with getting a meteorite classified has been a hot topic among collectors and dealers alike lately. They feel that now may be the time to get some classifications done, because many have invested in stockpiles small and large, or they may have found a rock that they suspect may be a meteorite. Meteorites as an immediately non-renewable resource are beginning to dry up from the hot deserts, and laboratory backlogs will soon be decreasing as the flow of meteorites from the Sahara and Oman has been seriously reduced.

The process of having a meteorite classified is not a simple concept to explain due to many variables, but I will try to address it with my personal experiences from a collector's standpoint. I think of every classification as being the second part of a treasure hunt. The first part comes from acquiring the stone, whether through finding it or purchasing it (more of the later in my case). The second part is sending out a type specimen for study and waiting like an expecting parent to receive the outcome, which can take many years in some circumstances. There are several built-in surprises that can be brought to light only by scientists and laboratories. I am getting ahead of myself here so I will start with the acquisition stage.

Finding A Suspect Meteorite

Many are introduced to the avocation of meteorite collecting by thinking they may have found one or by purchasing a specimen as a curiosity. This is how my interest started. I found a heavy black stone that was attracted to a magnet while prospecting for gold in the Washington State Cascade Mountains. When cut it displayed metal, something that I read about meteorites in a treasure-hunting magazine. I went online, read more about the subject and was convinced I had one. I devoured everything I could on the subject for eight months while the piece sat on my desk. I purchased a few modest genuine meteorite specimens and this was the start of my collection. After reading about the importance of classifications I decided it was time to contact a laboratory and have my piece studied.

Which Lab?

My big question was: where do I send it? I again went online and found a reference on the Meteorite Exchange. A gentleman was advertising an interest in Washington State meteorites, as only five have ever been found. I contacted him and he suggested I take it to the University of Washington (UW), Department of Earth and Space Sciences. This is where I met Drs. Tony Irving and Scott Kuehner, the start of a very productive relationship.

Lab Results and More

I made arrangements to have Dr. Irving look at the stone and took it to the UW lab. At first, he did not know what to make of it so he made arrangements to have it studied using an Electron Microprobe. The outcome was not what I wanted to hear, but I accepted his conclusion: the stone was a rock from the Earth's mantle with high amounts of magnesium-rich chromite, which is magnetic and highly refractory, explaining the similar appearance to a meteorite. I was told I could name the type of rock so I decided to call it Teananite, because it was found in the Teanaway River. Dr. Irving went on to tell me that he has looked at hundreds of prospective meteorites over the years, and that this was the best meteorite wrong he had seen. Instead of discouraging me, he invited me on two meteorite-hunting expeditions in Eastern Washington and later to the Burgess Shale in the Canadian Rockies for a Geology 490 class. We had a lot of time to discuss meteorites on these expeditions and that is where the goals were made. The seemingly impossible goal of finding a new Martian meteorite was set and then realized two years later with NWA 1195.

Thousands of Meteorites

As my interests grew, I started investing in purchasing trips to Northwest Africa. One of these produced a lunar meteorite, forever sealing my fate as a meteorite collector. It finally escalated to the point of setting up direct contacts in the Sahara Desert and several buying missions to Morocco. Over the years my brother, Greg and I have brought out thousands of meteorites on these trips, and with the help of the UW were able to have hundreds of them characterized. One of our initial goals was to have each and every one classified, but this became an overwhelming project as they were coming in faster than we could process them. Since then over a dozen scientific institutions have been involved with the study of our material. They all have their own specialties and tools, so many institutions may be involved with a single classification.

First Steps

The point of all of this is to emphasize that you should find a qualified lab you are comfortable with. I liken it to shopping around to have your vehicle repaired. You may want to start in your area or submit it to a university in the state, province or country in which it was found. Many laboratories do not have the funding to study each and every piece, so you may have to pick one that charges. Fees can be as low as $50.00 all the way up to several hundred dollars depending on the complexity and amount of time involved in the classification process. If there is additional scientific interest and if more testing beyond classification is required, there are usually no more associated costs.

The best place to start is the Meteoritical Society site where qualified institutions are listed. Do not be shy about sending off an email or letter inquiring about what services are provided. If they are not interested, they may be able to direct you to a laboratory and scientists in your area that will perform the classification. If you have multiple items to classify over time, it would be wise to build a mutually beneficial and respectful relationship with the laboratory, so that the procedure will be smoother the second or third time around. Do not ask if they can do a hundred classifications at once; two or three is an acceptable goal for one session. By all means, do your best to make sure what you are sending in is an actual meteorite or scientists may not take you seriously the next time. If you are not sure, state this and see if they are willing to at least take a look at it. If they agree to look at it and say it is not a meteorite, do not argue with them, accept it and move on to the next stone.

Here is a link to the Meteoritical Society list of institutions (will open in IE):
http://meteoriticalsociety.org/bulletin/institutions.pdf

It is best to pick from this list and google more information online for more detailed contact information. It would be impossible for me to list every institution in the world capable of doing classification work, so a little bit of research will be necessary.

Requirements

There are many reasons why a collector or dealer would want to have a meteorite classified but there is not enough room here to address this. Once you have a meteorite in your hands and you know who you want to classify it, the following will be required.

If the coordinates are known, they need to be provided. If not known, it needs to be stated where it came from even if it was purchased with no first-hand find information. The date of find is required. If not known, then the purchase date will have to do.

The weight of the stone must be recorded. If multiple suspected meteorites from the same event are found, the weight of the entire batch and how many were found must be recorded. The lab may require that each and every meteorite be inspected for pairing purposes.

A proper type specimen must be deposited for study. It must weigh either 20 grams or 20% of the Total Known Weight (TKW), whichever is less. It is best to send a sample that shows as many attributes as possible, because in some cases 20 grams is not enough for the lab to properly characterize it. Do not be too stingy. It is acceptable to deposit more than the required amount if additional items of interest may be revealed. This can only enhance the value, both from an intrinsic and scientific standpoint.

At this point, there is little the submitter can do but wait patiently. It is not good to bother the scientists, as most I have met are extremely busy individuals. They seem to travel more than the average person, in many cases managing a hectic class schedule as well as being busy with their personal life. I think it is acceptable to contact them every six months or so to check the status, or perhaps every three months if you are paying for the service.

Iron and Stone

This is what will happen next provided the meteorite is not of an iron type. The procedures for studying iron type meteorites include irradiation in a nuclear reactor and then counting particles given off after the material has sufficiently cooled down (radiation dying down to the point where measurements can be taken). Needless to say, this is a very time consuming process and the experimental reactor may only be fired off a few times annually adding more delay.

Other meteorites will be treated in a different manner. A thin-section will be cut from the type specimen for optical characterization if it is indeed determined to be a meteorite. Laboratories will sometimes send out a piece to have thin-sections made because they may not have in-house capabilities, or they may require a calibrated specimen suitable for petrologic or microprobe study. This process can take months if not handled directly at the classification facilities, and there may be a nominal charge for this service (~U.S. $30.00) or more if it is expedited.

Sometime during this process, the scientist will request a provisional name assignment from the Nomenclature Committee operating under the Meteoritical Society based on the information you provided.

More than likely, next it will be studied under a petrologic microscope. Attributes like shock, metamorphism and the degree of weathering will be noted.

Then it will be analyzed using a Microprobe so that the mineral chemistry is understood. This is where the main class can be determined. If the results are not clear at this stage, then a sample may need to be sent out for oxygen isotope studies to properly group it. This can take up to 6 months or a year because very few facilities with meteorite expertise exist.

The Meteoritical Society

The scientists will compile all of the data at this point, determine the proper contact at the Meteoritical Society's Nomenclature Committee and then submit the information for peer review. The committee may ask for more data after reviewing the classification submission or may send it on for a vote. The classification will remain provisional until the committee votes on it, which could take months since they only meet a couple of times a year. After a yes vote, the assigned classification then will become official and your name will be listed in the Meteoritical Bulletin as the main mass holder.

In closing, this may sound like a daunting task but it becomes easier with time. It is a learned process, one that will provide satisfaction and enhance the pleasure of collecting. It offers the rare occasion for collectors and scientists to work together in a collaborative effort for their mutual benefit. In that spirit I would like to take this opportunity to welcome Dr. Harold C. Connolly Jr. aboard the IMCA. He serves as the editor of the Meteoritical Bulletin and no doubt will be able to provide valuable insights regarding Meteoritical Society guidelines, which the IMCA adheres to and encourages among its members.

Happy Collecting!

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