Representative microphotographs of hornblendite TUL3 (a), hornblende gabbro TUL1 (b), hornblende-biotite quartz diorite SAJ12A (c) and hornblende-biotite tonalite MAR1 (d). Despite post-magmatic alteration, igneous textures are generally preserved (a, b, c) but a weak foliation can develop locally (d). Note the interstitial epidote-apatite-zircon-biotite cluster in sample MAR1 (d).