  The development of residual strains within a material is a valuable
engineering technique for increasing the material's strength and toughness.
Residual strains occur naturally in some biominerals and are an important
feature that has recently been highlighted in biomineral studies. Here, we
review manifestations of internal residual strains detected in biominerals. We
describe the mechanisms by which they develop as well as their impact on the
biominerals' mechanical properties. The question as to whether they can be
utilized in multi-scale strengthening and toughening strategies for biominerals
is discussed.
