Crusted individual
A whole, unbroken meteorite that is still covered with the dark fusion crust it gained during its fall.
A crusted individual is a single complete meteorite, not a piece broken off or sawn from a bigger one, whose outer surface is still covered in fusion crust. That crust is a thin layer, often less than a millimetre thick, made when the outside of the falling rock melted in the atmosphere and then hardened. On fresh stony meteorites it is usually black and either matt or glossy.
Collectors and scientists value crusted individuals because the outside records the meteorite's flight. Some show shallow thumbprint-like dents called regmaglypts, flow lines of melted rock, or a cone shape that tells you the stone kept the same face forward as it fell. When a fireball breaks up, it can scatter many individuals across a strewn field. Many small crusted stones were picked up after the Chelyabinsk fireball over Russia in 2013, and the Sikhote-Alin iron shower of 1947 left individuals with beautiful regmaglypts.
To recognise one, check that the crust covers all, or nearly all, of the surface. A small broken patch can still count, but a cut or sawn face means it is no longer a true individual. Store individuals dry and handle them gently.
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Level: Explorer Ages 10 and up