In this work, the effect of temperature on the texture of higher basicity calcium silicate hydrates, alpha-C2SH, kilchoanite and hydroxyledgrewite is presented. Calcium silicates hydrates were synthesized under hydrothermal conditions in the primary mixtures which consisted of calcium oxide and amorphous silicon dioxide. The N-2 adsorption/desorption isotherms showed that both meso and macropores are present in synthetic alpha-C2SH and hydroxyledgrewite samples, while kilchoanite is a non-porous material. It was calculated that a synthetic alpha-C2SH sample has a two times higher specific surface area (33.81 m(2)/g) compared to kilchoanite and hydroxyledgrewite samples. The TEM micrograph of alpha-C2SH and hydroxyledgrewite samples showed platelike crystallites, while fibers were observed in the kilchoanite sample. It was determined that calcination influenced both the surface area and the shape of crystallites of all the investigated samples. The obtained results were confirmed by data of nitrogen gas adsorption, scanning electron microscopy and transmission electron microscopy analysis. (C) 2019 Elsevier B.V. All rights reserved.