Abstract: The mortar composition for fixing an anchoring element in a drilled hole in a substrate consists of a water component and a mineral mortar paste held separately from the water component in a crushable container. The mineral mortar paste includes a mixture of mineral mortar and a liquid solvent chemically inert towards the mineral mortar and the mineral mortar paste is hardenable with the water component to form a hardened mortar compound. The water component consists of water and a thixotropic agent so that the water component acts like a paste when not subject to shear forces but flows when subject to shear forces such as those created by the anchoring element advancing in the drilled hole. The thixotropic agent is advantageously amorphous pyrogenic silicic acid.