MERCURY MINING
Ore indications with red cinnabar deposit (HgS) in the boundary region of Cervenica and Zlata Bana are situated on extensive territory. I tis an irregular ore genesis process occurring in certain wide propylitised andesite belts; close to the surface. From available sources in archives and literature it cannot determined if deposit is having any distinctive form.
According to direct and indirect proves; red cinnabar can be considered a mineral that was the object of exploitation and followed usage in mercury production, as early as the 15th-16th centuries.
The first particular record which remarks on mutual exploitation of red cinnabar and opal is from 1791 by Fichtel, J.E.; on the basis of a document from 1400; at that time situated in Kosice Chamber Archive.
Another source from 1568 by an unknown author; published by Szamota in 1894. The document considered by Szamota is the oldest mining file written in the Hungarian language. At the time of publication it was situated in the State Archive in Budapest. The unknown author in the document mentioned several locations of Hg exploitation, however does not delimit locations topographically any further. There is no doubt this is the same territory of mutual exploitation of red cinnabar and opal, that Fichtel later wrote about.
According to the document from 1568 the mines had no activity, were ruined, and the village of Cervenica abandoned. Merely old remains of the mining site were reexplored and processed. The document is interesting in the author's detailed description of the technology adjustments and smelting of mercury ores.
Old abandoned mercury mines in Cervenica, Libanka hill; are pictured in the old map from 1745 made by state registrar in Solivar. There is no more information on mercury mining in the later period of time, except the dump explorations in 1830, 1837 and 1852.
According to late authors such as Richhofen, F. in 1860, Hungalvy, J. in 1863 and others. There is a remark about mercury mining such as that mercury was exploited successfully in the past by re-calling the earlier authors.
In fact we can state that mercury mining in the region of the mentioned villages was realized most intensively in the 15th and 16th centuries; then suddenly fell down, and never had been recovered. All attempts to revive this by later prospectors had no success.
Geological research done in 20th century confirmed the deposit of cinnabar ore, but object deposit could not be considered an economically prosperous.
Cinnabar exploitation and its following smelting at the deposit area were done only in the 15th and 16th centuries. The ore parts were exploited to the depth of only a few meters with compliance of side mineral, work proceeding, and technique used at that time. Locally and most rarely as a result of this activity “pingy” can be found, “pingy” are funnel pits with various depths of up to 100-120 cm and 200-300 cm wide in the opening, covered with vegetation.
Classic underground mining could not have been taken into consideration at that time and the territory. All work related to cinnabar mining was done manually. The ore was carried, separated, crushed and washed by hands in wooden tubs. The work related to ore mining, smelting and its distillation had typical seasonal characteristic and was not done during the winter months.
SMELTING
According to, up to date discoveries and territorial survey, literary descriptions and others; the process of mercury production was quite simple. This was done in stoneware called retorts, made of earthenware.
Stoneware vessels were handmade by potters on a pottery wheel. A necessary accessory to this stoneware vessel was a small bowl measuring 8-9 cm in diameter, and 3+ cm high. The stoneware vessel itself had the form of a pitcher with a tubular neck. The height of the vessel was about 30 cm, the maximum height of the body 12-15 cm, and measured 8 cm average in diameter at the base.
The vessel was filled with a crushed cinnabar ore, plugged at the neck with moss, covered with a bowl and pasted with clay. The retort was then placed upside down (the bottom up) in the prepared roasting area. The stability of the vessel during wood and fire manipulation was secured with wooden pickets, about 3 pieces. The wooden pickets prevented damage of the pasted part of the bowl with the neck of the vessel; as this should have protected the releasing of Hg fumes.
Filled and picket-secured retorts were placed in rows, numbers ranged from 200-300 pieces to the “roasting” area, which created one battery. The retorts set in the battery were filled with half a layer of mineral; this created a condensate layer. The top half of the vessel height was covered with firewood and set on fire.
By roasting the cinnabar sublimated, the mercury fumes had released from cinnabar ore in the neck of the vessel. The mercury was collected in the bowl; this resulted in the end of the process of distillation. The retorts were mostly broken up at the neck, and burnt cinnabar was re-used as a new condensate layer. Collected mercury after the washing and cleaning process presented the final product. The whole process of mercury distillation lasted 2-3 hours depending on various factors. The slag left by the smelting contained 0,4 - 0,5 % of Hg, depending on the quality of cinnabar ore; the pile of slag was often a valuable material for re-using.