In this study we examine the accuracy of the level method, the overflow method and the mass-based suspension method in determining the density of natural stones. We find that the density of polycrystalline materials, which is challenging to be determined by conventional crystallographic techniques (X-Ray diffraction, neutron diffraction), which are the most accurate methods of determining densities of single crystals, can instead be assessed accurately using a mass-based method and inexpensive instruments. In addition, the methods we explore are non-destructive which preserve the natural stones. The density is determined with a mass rather than a volume determination method based on the suspension method that uses Archimedes principle. This method is found to be the most inexpensive and accurate to assess the density of natural stones accurately to two decimal places (±0. 01 g cm⁻³) with costs of equipment that range between 20-30. In addition we provide details of the design of a new liquid-based pycnometer that can measure the density of irregular shape natural stones without the need to form a powder of the rock. This pycnometer can also be used to measure density changes in liquids as a function of temperature and solute concentration. The method described in this manuscript can find applications in science education but also commercially by collectors and merchants of natural stones.
Loizidou et al. (Wed,) studied this question.