Sometime late last century I purchased a chunk of Gibeon iron from Blaine Reed. It was a very well formed complete individual that contained many of the features I needed. Yes, needed. For this particular iron was going to earn its keep as a tool for teaching about the solar system.
Since that time, literally thousands of students young and old have got their hands on this Gibeon as their first intimate experience with a real meteorite.
So what were the features I selected for this teaching iron?
Backing up a step, I did not simply buy any old iron sight-unseen, nor get the most pounds for my bucks. Instead I considered what the specific teaching needs and demands on such a meteorite would be. Sure, waving around a square centimeter of SNC can be jaw dropping, but that’s more a shock of faith than a visceral reaction to physical interactions. What I wanted was something that the students could play with, yet not threaten the iron or their own safety. Plus the iron must be portable but massive enough to let gravity do the talking.
Got A Pic?
Because the internet was still in diapers, Blaine Reed mailed me some Polaroid pictures of potential candidates given my list of needs. After a little back and forth, I settled on a 25 pound Gibeon of particularly solid construction with a lightly symmetrically and ovalish form. The surface was filled with quality and representative thumb printing, but absent of any extraneous protrusions. The smooth but undulating surface was appealing to the eye, and characteristic of iron meteorites without introducing rare but memorable features such as holes, orientation, protruding inclusions, or cut faces that can confuse the topic.
While unique or unusual features are interesting and certainly part of the world of meteorites, they can also become the rule of the exception. In other words, those cool, valuable and highly desired bits of meteorite uniqueness can distract from the initial learning about rocks from space. For example, I once showed a handful of chondrite slices to a high school class only to have the teacher comment that she never knew that meteorites were so flat! Needless to say, I didn’t see that one coming. Or another oxymoron of meteorite identification is that most stone meteorites are attracted to a magnet…unless they are of the highly desirable achondritic variety. A side note on this sidebar is that early hot desert nomad trainers show the locals how to use magnets to ID possible meteorites. But it didn’t take long for the nomads to realize that the non-magnetic suspects might be the most valuable which is why the flood of achondrites appeared much later after the Great Saharan Meteorite Rush. And more than a few meteorite dealers scored big by buying the magnetic-attracted stones and getting the “duds” for free or pennies on the gram.
The weight and shape of the iron were critical for what I had in mind. First, the weight must be enough to shock handlers, but not so much to prevent mobility. And the shape must prevent easy grip on the iron. Yes, prevent it. At 25 pounds, the iron is not something that can easily be picked up by a student, let alone with one hand which just happens to be my rule when the meteorite is at the center of a group of students. Adding to the struggle of lifting the iron is that it is fairly smooth and somewhat slippery from human hands and occasional cleaning and oiling.
When presenting the iron to a class of students from preschool to college-age, I usually pull the iron out of its bag and drop it a few inches onto a piece of carpet or desktop. The aggressive thud planted the seed that this thing is heavy, well actually dense. I then roll the iron around to show off its form, as well as demonstrate the intersection of explorative curiosity and respect the students must have for this particular meteorite.
Gibeon Can Vote
Fast froward 20+ years, and the Gibeon is no worse for wear, yet has enriched many lives and impressed thousands of meteorite-curious students. As a representative of an asteroid, a meteorite, a model for the core of the earth and a possible building block of life, this a simple-shaped, molecularly-boring lump of nickel-iron metal, this humble Gibeon iron has done more than its share of work as an interplanetary ambassador.