Aotea

The rock is a variety of kyanite-plagioclase schist as classified by McClintock and Cooper (2003), distinguished by bright bluish-green to green bands; the diffuse green (fuchsite-dominated) and blue (kyanite-dominated) horizons intercalated with white quartz/plagioclase on a millimetrescale. As yet, although no actual outcrop of this particular rock variety has been found, McClintock and Cooper describe float boulders in Kini Creek where this lithology is shown interlayered with the kyanite amphibolite exposed as in-situ stream outcrop. Mineral components of the ‘kyanite-plagioclase’ samples examined by McClintock and Cooper are: quartz – plagioclase - chromian muscovite (typically known as fuchsite) - kyanite +/- talc +/- scapolite +/- margarite, and specimens I have examined may also contain small amounts of phlogopite and chlorite. The characteristic green colour of the fuchsite, and therefore the important component of aotea stone, is due to presence of 0.82 - 0.90% Cr2O3; the 'malachite-amazonite-like' samples found in the Makawhio River are thus specimens rich in fuchsite.