For the longest time, the idea that rocks would fall from the sky was dismissed as claptrap and fantasy. But rogue fragments in space can, and do, impact the earth with surprising frequency. Most meteors that enter the atmosphere are quite small–the size of a grain of sand–and we see them as “falling stars,” burning up before reaching the ground. But some are big enough to survive the burnout of entry into the atmosphere and impact the earth’s surface as a meteorite.
Most meteorites are stony or composed of iron or other metal alloys. But among the rarest of meteorites is a form known as pallasite. This is basically a “fruitcake” from outer space, where an iron/nickel matrix is suffused with gem-like champagne-colored crystals of olivine, which are often “shattered” due to physical impacts after solidifying.
So what makes pallasite so rare? Well, first an object in space that is cooling and has molten iron/nickel and olivine crystals needs to be struck by another body, causing the crystals to disperse into the metal matrix. This hardens, and eventually a few of these oddball meteors makes it through the atmosphere to impact earth’s surface. Those that survive the impact without being disintegrated are then subjected to hundreds, thousands, or tens of thousands of years’ worth of weather…. rainfall, etc. that can rust away the iron matrix into dust, causing the beautiful fruitcake to disintegrate.
The value of pallasite is consistent with the story of all meteorite specimens: if new ones fall, or old ones are found, the supply increases and the cost of acquiring a specimen goes down. I acquired a slice a number of years ago, after new examples had been found and harvested. This specimen is shown here.
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