Several hypotheses regarding the variety of functions fulfilled by the seven wooden troughs found until now in the prehistoric salt mines at Băile Figa, Bistrița-Năsaud County, Romania and dated in the Bronze Age, have been advanced. However, until now, no valid and convincing arguments in favour of a functional system in which troughs could be understood as part of the rock salt and brine extraction and/or exploitation processes, have been presented. Even if their connection with the salt areas is indubitable, because they were usually discovered in secondary contexts, their exact application was not immediately apparent.
The hypothesis according to which the troughs were used as part of a system meant to direct streams of water to aid in the piercing of salt rocks, belongs to E. Preissig, who developed it in 1877. Although partly agreed by researchers up until 2010. It was our experiment in 2010 that clearly proved the efficiency of the troughs system in perforating salt rocks by fresh water. Between 2017–2018, more archaeological experiments were completed within the project EthnosalRo3 in the site of Beclean - Băile Figa. They have proven that the wooded troughs and structures, utensils and tools associated to them, are effective for: rock salt extraction, brine evaporation (brine evaporation in troughs is possible using hot stones), salt mud filtering. During the experiments we used three precise replicas of the wooden troughs found in Băile Figa (one small and two large), worked by specialized craftsmen from the exact tree species as the originals. Several positions and heights were tested, as well as the application of throughs in individual or group arrangements. Chemical analyses of the brine obtained in different times and ways are provided.
Chemical analyses of rocks, minerals, and detritus, Yucca Mountain--Preliminary report, special report No. 11