Hydrotalcite and hydrocalumite are two close minerals belonging to the layered double hydroxide family. Both structures are based on positive brucite-like layers alternating with layers containing anions and water molecules. Most of synthetic (LDHs) are hydrotalcite-like materials. On the other hand, the hydrocalumite structure type is rare for those less broad in composition, typically Ca 2 + and Al 3 + in the hydroxide layers. In order to get further insight into the conditions of stabilization of this structure type, we have undertaken the synthesis and the structural characterization by powder X-ray diffraction of the series Ca 2 M 3 + (OH) 6 Cl.2H 2 O(M 3 + :Al 3 + , Ga 3 + , Fe 3 + and Sc 3 + ). The incorporation of Sc 3 + ions is quite original. All phases crystallize in the rhombohedral space group R-3 resulting in a three-layers polytype. The main consequence of the replacement of Al 3 + cations by large M 3 + cations is a compression of the octahedral layers like it proceeds in hydrotalcite-like materials. The existence of Sc-containing phase allows us to say that it is the size of Ca 2 + ions and the pronounced anisotropy of coordination spheres around Ca 2 + and M 3 + which are responsible for the ordered distribution of cations in hydrocalumite-like materials.