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"Diabantite, ore material, and agate in vesicle of main basalt. The radial mass occupying the center is diabantite, the opaque material surrounding it is magnetite or ilmenite, and the outer rim is agate." -Walcott, 1901

Diabantite

"Diabantite, ore material, and agate in vesicle of main basalt. The radial mass occupying the center…

"Isometric. Octahedral habit, sometimes twinned octahedrons. Dodecahedron at times, either alone or with octahedron." — Ford, 1912

Magnetite

"Isometric. Octahedral habit, sometimes twinned octahedrons. Dodecahedron at times, either alone or…