Limburgite
“Glassy basanite with no feldspar”
Limburgite is a dark, glassy volcanic rock similar to basanite but containing virtually no feldspar — only olivine and pyroxene phenocrysts set in a matrix of dark volcanic glass with nepheline. It represents some of the most silica-poor lavas erupted at continental volcanic centers.
olivine (phenocrysts), augite (phenocrysts), volcanic glass, nepheline (groundmass), magnetite, perovskite
Limburg (Kaiserstuhl, Germany — type locality), Hegau (Germany), Eifel (Germany), Auvergne (France), Victoria (Australia)
5-5.5
Limburgite is named after Limburg hill in the Kaiserstuhl volcanic complex of southwestern Germany — a region where almost every variety of alkaline volcanic rock can be found within a few square kilometers.
Test Your Knowledge
Why does limburgite contain volcanic glass rather than crystalline feldspar in its groundmass?
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