Figure F25. Photomicrograph showing a completely talc-altered rock in which the original (hourglass?) serpentinite microtexture is still preserved even though the serpentine has been completely replaced by talc (Sample 209-1268A-8R-1, 117–119 cm) (cross-polarized light: blue filter; field of view = 1.4 mm; image 1268A_051).