FIG. 13.

Scanning electron microscope images of pink hexagons. (A) Overview of a field of pink hexagons. (B) Closer view of one of the hexagons that shows some degradation of the hexagon. (C) Close-up view of detail from (B), showing the coated filaments inhabiting the upper surface of the hexagon. (D) EDX analysis of the hexagons showing the presence of iron oxides and a possible opal coating (Si, O). (E) Close-up view of the coated filaments that inhabit the surfaces of hexagons. (F) Small- and large-diameter filaments have colonized the basaltic glass between hexagons. Color images available online at www.liebertonline.com/ast