The yolk sac equipped with vitelline fluid, plays a crucial role in supplying nourishment to the developing chicken embryo during embryonic and early postnatal development. The absorption and utilization of calcium in embryogenesis has been investigated for years. However, the preservation process of the calcium as it is transported through the chorioallantois membrane during embryogenesis remains largely unknown. In this study, we demonstrated that abundant liquid crystal droplets (LCLD) subsist with calcium carbonate vaterite crystals (CCVC) in the yolk sac, revealing a possible function of LCDL in CCVC crystallization.