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NUMBER 19
sents a break in the main mass late in the highvelocity
flight, but while the meteorite was still
falling fast enough to form fusion crust. The sharp
edges around this face have been only slightly
rounded, indicating a brief period of ablation.
6. This stone not only has an unusual flat square
face but also has other surfaces which are almost at
right angles to it (Figure 3). Thus there are three
rectilinear directions represented in the surfaces of
the meteorite.
7. The shape of this mass, therefore, shows that
the meteorite broke up during high-velocity flight.
After each break the object adjusted its position so
that its center of gravity and the stagnation point
on its front face were on the line of fall of the
meteorite. The weight of the object decreased by
spallation and ablation, and its velocity was
decreased to free-fall velocity by atmospheric
friction.
The morphology of this meteorite shows that
other fragments must have fallen as individual
stones along its trajectory. None was recovered,
however, probably because the brushy terrain made
search and sighting difficult.
Structure and Mineralogy
When viewed with the naked eye, a broken
surface of the meteorite appears remarkably homogeneous,
the material being compact and pale
gray. With a hand lens brightly reflecting particles
of nickel-iron and troilite are seen dispersed
FIGURE 4.—Photomicrograph (reflected light) of a polished surface of the Harleton meteorite;
metal particles are white, troilite (and chromite) pale gray, silicates dark gray. Greatest dimension,
2,0 mm.
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