Diffraction contrast in X-ray radiographic images of octahedrite meteorites

Slices of similar to 12 mm thickness cut out of an octahedritic iron-nickel meteorite of the Gibeon shower were investigated by conventional X-ray tra nsmission radiography. When the direction of the incident X-ray beam is par allel to one or two of the four habit planes of the kamacite lamellae, blac k-white contrast lines are observed in the radiographs. These lines are att ributed to Bragg reflection, at lattice planes parallel to the lamellae pla nes, of a narrow band of wavelengths filtered out of the incident white spe ctrum by absorption in the sample.