Like many other Martian basalts in the world’s meteorite collections, it probably formed as a basalt flow at or near the surface of Mars. The unusual “poikilitic” texture of this rock is marked by large crystals of pyroxene (a magnesium-iron silicate) enclosing small crystals of olivine (a magnesium-iron silicate) and chromite (an iron-chromium oxide). The texture most likely formed by rapid cooling of the rock from magmatic temperatures. The feldspar mineral grains (a calcium-aluminum silicate) have been transformed into glass, a mark of the intense shock pressure experienced by the rock when it was blasted off the surface of Mars by an enormously energetic impact event.

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