Fig. 2
From: The use of mineral interfaces in sand-sized volcanic rock fragments to infer mechanical durability
Data-acquisition of counted interfaces under the polarizing microscope: line counting and definition of interface frequencies. a, d, e No-isostructural interfaces with a dominant glass-rich groundmass; b, c and f No-isostructural glass-poor interfaces with a dominant microlitic groundmass and minor black glass. Qz = Quartz; Pl = Plagioclase; Ol = Olivine; Px = Pyroxene; Hbl = Hornblende; Bt = Biotite; Op = Opaque; Glgr = Glassy groundmass; Migr = Microlitic groundmass; + = optical microscope crosshair; Volcanic grains sketches from a hyalodacite, b pyroxene-andesite, c olivine-bearing basaltic andesite, d rhyolite, e basaltic andesite, to f glomeroporphyritic olivine-basalt, are modified from Williams (1950)