We report a new type of högbomite in a spinel- and sapphirine-bearing silica-deficient Mg-Al rock from Manavadi at the northern margin of the Madurai Block along the Palghat-Cauvery shear zone system, which defines the Archaean-Proterozoic collisional boundary in southern India. Högbomite occurs here as fine- to medium-grained euhedral to subhedral crystals enclosed within or along grain boundaries of greenish spinel. It is compositionally very unique due to the lack of TiO2 (<0.2 wt.%) and enrichment in Al2O3 (66.4–70.8 wt.%) compared to other occurrences. The variety of högbomite described in this study, confirmed by laser Raman spectroscopy, has not been reported elsewhere previously. Högbomite in this study is subdivided into three groups based on the
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