Rodingite
“Calcium-enriched by serpentinizing fluids”
Rodingite is a calcium-rich metamorphic rock that forms when mafic rocks like gabbro or diabase are infiltrated by calcium-bearing fluids released during the serpentinization of nearby ultramafic rocks. The result is a pale, dense rock packed with calcium garnet and other unusual minerals.
grossular garnet (hydrogrossular), diopside, vesuvianite, prehnite, chlorite, epidote
Rodding River (New Zealand — type locality), Liguria (Italy), Troodos (Cyprus), Northern California (USA), Hokkaido (Japan)
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Rodingite dykes stand out as pale, resistant ridges within dark serpentinite because they're so much harder than the surrounding rock — they weather in relief like geological ribs.
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