Volcanic rocks which have been observed include absarokite, andesite, basaltic andesite, hornblende-lamprophyre, minette and spessartite.
2.
Volcanic rocks of the absarokite-shoshonite-banakite series described from Yellowstone Park by Iddings and the similar ciminite-toscanite series described from western Italy by Washington are associated with leucite-bearing rocks, potassium-rich trachytes and andesitic rocks.
3.
Textural and mineralogical features of potash-rich basaltic rocks of the absarokite-shoshonite-banakite series strongly suggest that most of the large crystals and aggregates are not true phenocrysts as previously thought but are xenocrysts and microxenoliths, suggesting a hybrid origin involving assimilation of gabbro by high-temperature syenitic magma.
4.
On a purely chemical basis, an extrusive lamprophyre ( sp . " minette " ) might be classified as potassic trachybasalt, shoshonite, or latite using the total alkali-silica diagram ( see TAS classification ), or as absarokite, shoshonite, or banakite using a classification sometimes applied to potassium-rich lavas.
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