Trachyte is the most common rock on Mount Takahe, phonolite being less common. Basanite, hawaiite, and mugearite are uncommon, but the occurrence of benmoreite and pantellerite has been reported, and some rocks have been classified as andesites. Hawaiite occurs exclusively in the older outcrops, basanite only in parasitic vents and mugearite only on the lower sector of the volcano. Despite this, most of the volcano is believed to consist of mafic rocks with only about 10-15% of felsic rocks, as the upper visible portion of the volcano could be resting on a much larger buried base. The parasitic vents probably make up less than 1% of the edifice. Ice-lava interactions produced hyaloclastite, palagonite and sideromelane. No major changes in magma chemistry occurred during the last 40,000years but some variation has been recorded.