Photographs of Fe–Si–Mn oxyhydroxides at Franklin Sea-mount. (a) In situ fresh staghorn chimney spire taken from submersible. Note the mottled pale color of the oxyhydroxides becomes more reddish towards the base (see arrow), (b) hand sample of oxyhydroxide taken on ship deck exhibiting red ferric iron with a sooty black manganiferous exterior. Photographs 2a and b courtesy of Raymond Binns, CSIRO, Australia. Thin section photographs of Fe–Si–Mn oxyhydroxides from Franklin Seamount. (c) and (d) iron mineralization attached to hair-like structures, sample M2192 loc. 1 (106848), note the faint outline of the filaments in association with the structures (see arrows), height of images 70 μm. (e) Filaments exhibiting a branching morphology (see arrows), sample M2157-14a (106893), height of image 70 μm. (f) Filaments exhibiting a bunched morphology, M2157-14a (106893), height of image 170 μm.