Both intact and fragmented, but recognizable shells and skeletons are known as allochems. Finer-grained mud-sized particles initially lithify to micrite and can later recrystallize to microspar or ...

Packstone - A packstone is a rock where grains touch and form a framework, and contains micrite or recrystallized micrite (microspar or pseudospar) between the grains. Paleozoic Invertebrates - These ...