Leucitite
“Potassium-rich lava with white crystal eyes”
Leucitite is a rare potassium-rich volcanic rock containing abundant leucite crystals — distinctive white, trapezohedral grains that stand out against the dark groundmass. It erupts from some of the most potassium-enriched magmas on Earth, typically in areas with unusual mantle compositions.
leucite, clinopyroxene (augite), olivine, magnetite, apatite, nepheline
Vesuvius (Italy), Alban Hills (Italy), Leucite Hills (Wyoming, USA), Gaussberg (Antarctica), East African Rift
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The Leucite Hills of Wyoming contain some of the most potassium-rich lavas on Earth — they erupted as recently as 300,000 years ago from a source completely unrelated to the nearby Yellowstone hotspot.
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