The renewed interest in lunar exploration has increased research efforts in lunar in-situ resource utilisation (ISRU), which involves using locally sourced materials to reduce reliance on expensive and complex Earth-based logistics. Lunar regolith, a loose layer of fragmented rock covering the Moon’s surface, often many metres thick, is the primary ISRU material due to its abundance and accessibility. It can, for example, be used to construct infrastructure, extract consumables, and produce secondary goods. Lunar regolith analogue materials (simulants) are fundamental for developing and testing such ISRU technologies in laboratories on Earth before they are applied to other celestial bodies. The composition of the regolith on the lunar surface varies greatly in terms of its mineralogical, chemical, and particle type composition. Current simulants fail to adequately replicate this variability. Therefore this study introduces a flexible simulant system capable of tailoring simulants to different applications. The lithic base simulants LX-T100 (anorthosite) and LX-M100 (basalt) represent the Moon’s two major bedrock types and serve as the foundation for this system. In this study, these base simulants are comprehensively characterised in terms of their mineralogy using XRD, chemistry using XRF, particle size distribution by dry and wet sieving, laser scattering, and dynamic image analysis, particle morphology via image analyses, maximum, minimum, bulk, and solid density using a tapped volumeter, Scott volumeter, bulk density funnel, and pycnometer, respectively, and from these the void ratio and porosity are calculated. It is shown that the base simulants are good analogue materials for lunar soil. In Europe, in particular, the LX simulants aim to address the poor availability of suitable simulants.