“…Carbonate rocks are widely recognized to have microstructure, and in particular pore structure, that is significantly more complex than siliciclastic rocks (Choquette & Pray, ; Folk, ; Lucia, ). Hence, pilot laboratory studies mostly selected relatively pure carbonates (i.e., close to 100 wt % calcite) and focused on somehow simpler end‐members such as micritic (Nicolas et al, ; Vajdova et al, ), allochemical (Dautriat et al, ; Vajdova et al, ), microporous (Regnet et al, ; Baud et al, ), or macroporous limestones (Baud et al, ). The question of the impact of the composition and in particular the presence of secondary minerals (such as quartz or dolomite) on the strength and rheology of high‐porosity limestone has so far remained understudied, although high‐pressure, high‐temperature torsion experiments on low‐porosity synthetic limestones have shown that the addition of dolomite (Delle Piane, Burlini, & Kunze, ; Kushnir et al, ) or quartz (Rybacki et al, ) serves to increase the strength of limestone.…”