Fig. 8
From: The use of mineral interfaces in sand-sized volcanic rock fragments to infer mechanical durability
No-isostructural glass-rich interface between a phenocryst and a glassy groundmass (a-f) and isomineralic (e-f). a, b: Pl/Glgr interface (Plagioclase/Vesiculated glassy groundmass. a Crossed nicols: b Plane-polarized light: c, d: Hbl/Glgr interface (Hornblende/Glassy groundmass): c Crossed nicols: d Plane-polarized light: e, f: Ol/Ol (Olivine/Olivine interface) and Ol/Glgr (Olivine/Glassy groundmass) interfaces. e Crossed nicols, f Plane-polarized light. The hornblende basal cleavage system (c,d) constitute other preferential weakness planes of intracrystal breakage sites [10x, very coarse sand (2.00–1.00 mm)]