The effect of roll compaction/ dry granulation on the particle and bulk material characteristics of different magnesium carbonates and calcium carbonate was evaluated. The flowability of all materials could be improved, even by the application of low specific compaction forces. Roll compaction/ dry granulation resulted in a modified compactibility of the material and, consequently, tablets with reduced tensile strength. The degree of densification during tableting can be expressed as the ratio of the relative tablet density to the relative tap density of the feed material. Comparing the tablet properties of different magnesium carbonates reveals an obvious capping disposition. However, it depends on the type of magnesium carbonate, the specific compaction force and also on the tableting force applied. The microhardness of the ribbons was determined and mercury porosimetry was used to characterise the pore size distribution of tablets. A connection between particle shape, surface area and the resulting pore structure of the tablet could be shown for the four different types of magnesium carbonate. A screening was done to determine suitable binding agents. Mixtures of magnesium carbonate with different types of powdered cellulose (M80, P290, A300) were tableted directly or after roll compaction/ dry granulation. The fraction of powdered cellulose in the mixture varied between 0 % and 25 %. The properties of granules, blends and their corresponding tablets were analysed. The best flow properties showed granules with low amounts of A300. The Heckel-Plots showed clearly the different behaviour of powdered cellulose at the tableting process in blends and granules, respectively. The tablet pore structure was evaluated by mercury porosimetry. The addition of P290 and A300 into dry granules has refined the resulting tablet pore structure. High values for tablet tensile strength and low friability resulted from this special tablet structure. Granules and tablets of magnesium carbonate with 5 % of A300 were manufactured scaling up the process by a bigger roll compactor and a rotary tableting machine.