Acta naturalia Islandica - 01.07.1964, Síða 38

PLATE IV.
PI. IV a. Photomicrograph of the transition between normal grey and oxidized red
rocks ahove the quarry. The olivines are euhedral, the pyroxenes rounded. The olivines
are blacker in the red vesicular type than in the grey massive one showing various
degrees of exsolution. Plane polarized light x 10.
Pl. IV b. “Black olivine”. The i
clear zone between the rim and
the core is well seen. Note the
fine-grained groundmass, and
the good crystal faces of the
olivine. Plane polarized lightxlð.