Figure 2. (a) Wollaston Press developed in 1829 for compaction of loose platinum mud into a firm pellet [7]. (b) Extract from early work by Brill and Melczynski dated 1964 [8] on hydrothermal sintering. At the time, the authors did not intend to continue studies because they could not find any useful application. (c) Setup developed by Turba and Rump [9] for carrying out ‘cold sintering’experiments: a systematic correlation between strength of barite pellets and amount of water was found.