Recently, Bouville and Studart [35] synthesized nanosized CaCO3; vaterite with average size of 37 nm and agglomerated as 600 nm forms. The synthesized nano-vaterite together with water was subjected to sintering under pressures up to 800 MPa at RT. Relative density of 87% was obtained by 500 MPa pressure at RT, and the samples demonstrated 30 GPa elastic modulus, 50 MPa flexural, and 225 MPa compressive strength.