The main types of gold deposits in Romania

Romania is (was) known as a country rich in gold, richer as the most European countries. One area (the Gold Triangle or Quadrangle in Metaliferi Mts.) and several deposits/mines (Roşia Montană, Gurabarza/Brad, Bucium, Săcărâmb etc.) are worldwide known, due to the gold richness of the ores and in some cases as being type localities of some minerals, especially Au-Ag tellurides (e.g. Săcărâmb/Nagyag), respectively.
   The above mentioned deposit type is of hydrothermal origin and have been formed in relation to the Neogene, mostly subduction-related, volcanism. In addition, there are also gold deposits located in metamorphic rocks, mostly in the South Carpathians, which are shear-zone related. The third type is of alluvial origin; for some of them the source was identified but there are numerous deposits or occurrences with diffuse or dispersed sources. The latter are also distributed mainly in the South Carpathians.
   In addition to the above mentioned major gold deposit types, the gold production of Romania was based also on gold derived as by-product from polymetallic ores, mostly hydrothermal, situated in the northern part of Romania, related to the Neogene volcanism too. There are either gold-dominated deposits, e.g. Săsar, Valea Roşie, Dealul Crucii or polymetallic deposits with disseminated gold. In the Metaliferi Mts. (western part of Romania) porphyry type ores with a typical association Cu-Au, e.g. Bolcana-Troiţa, Voia, Bucium-Tarniţa etc., are also known.
   The gold production of Romania was however basically related to the hydrothermal ores belonging mainly to the Gold Quadrangle in the Metaliferi Mts. The famous deposits of the area, named “the New Eldorado” by McLaren (1918) are (were) not very large. Nevertheless, the veins are concentrated on small areas, with a high to very high frequency of ore veins per area. For example, the celebrated Au-Ag telluride deposit at Săcărâmb producing 300 kg Au per year, with an average Au content of about 9 g/t and Ag of 17 g/t (the period involved is before World War II), is developed on an area of only 1 km², on a depth of about 500 m. From the same deposit about 60 t of Te have been extracted. Locally, some gold vein were extremely rich, e.g. Musariu (13-19 g/t), Valea Morii (15-30 g/t). Roşia Montană is by far the largest gold deposit in Romania with a total of about 500 t of gold. Estimates by Roşia Montană Gold Corporation for the remaining gold to eventually be mined in open pit, range between 250 and 300 t.
   All the gold mines in Romania are now closed. Attempts are made to recover the nanogold from the waste dump material by different methods, e.g. by using suitable plants (an ongoing research project by the authors).
   A future gold resource could be also the gold presumably associated with BIF-like iron deposits, such as Palazu Mare in Dobrogea, a Krivoi Rog type deposit covered by a relatively thick, partly karstified, carbonate sequence.
   The gold production of Romania is best known from the period before the World War II; it varied from 4 t to 8 t of gold. Afterwards the gold production became secret and no public data were available until 1990. A figure of about 1-2 t/year is estimated for the last years. The gold fineness greatly varied from deposit to deposit. Older data give 500 ‰ for the gold from Roşia Montană and about 975 ‰ for the gold from alluvial deposits at Pianu (North Sebeş Mts.).