Third Worldwide Occurrence of Juangodoyite, Na2Cu(CO3)2, and Other Secondary Na, Cu, Mg, and Ca Minerals in the Fore-Sudetic Monocline (Lower Silesia, SW Poland)

Abstract

Na-Cu carbonates are relatively rare secondary minerals in weathering zones of ore deposits. Hereby we describe mineral composition and crystal chemistry of the most important secondary (Na)Cu minerals and their Na- and Mg-bearing associates forming rich paragenesis in Rudna IX mine. A non-bulky Ca-rich dripstone-like paragenesis from Lubin Główny mine is also characterized, using Powder X-Ray Diffraction, Rietveld, and Electron Microprobe methods. Light blue juangodoyite (3rd occurrence worldwide) and darker chalconatronite are the most important members of the Rudna IX paragenesis, being associated with malachite, aragonite (intergrown with hydromagnesite and northupite), and probably cornwallite. Most of the minerals are chemically close to their ideal composition, with minor Mg substitution in malachite. Cu chlorides are mainly represented by clinoatacamite and probably herbertsmithite. Additional, minor phases include trace Cu minerals langite, wroewolfeite, and a lavendulan-group mineral, and monohydrocalcite. Separate halite-rich encrustations are shown to be filled with eriochalcite, ktenasite, and kröhnkite. The most likely to be confirmed coexisting species include paratacamite, wooldridgeite/nesquehonite, johillerite, melanothallite, and kipushite. The Lubin paragenesis mainly comprises aragonite, gypsum, rapidcreekite, and monohydrocalcite, with trace vaterite. Blue colouration is mainly provided by a yet unspecified Ni-, Co-, Mg-, and Mn-bearing Cu-Zn-Ca arsenate mineral close to parnauite.

Rapidcreekite of anthropogenic origin - ’korkinoite’ from burnt mine dump in the Chelyabinsk coal basin, South Urals, Russia: crystal structure refinement, thermal behavior and spectroscopic characterization

“…Rapidcreekite was found associated with pickeringite and other minerals of the halotrichite group, MAl 2 (SO 4 ) 4 •22H 2 O, where M = Fe 2+ , Mg, Mn, Zn or Co (Onac et al 2013). Recently the mineral was described from the weathering zone of the Lubin mine, Lower Silesia, Poland (Kruszewski et al 2020). In general, the formation of rapidcreekite in nature is related to the low-temperature surface processes such as those occurring in hot springs (Roberts et al 1986;Wen et al 2020), weathering zones of ore deposits (Kruszewski et al 2020), karst caves and springs (Onac et al 2013;De Waele et al 2016;D'Angeli et al 2021) and even Arctic glaciers (Lau et al 2017).…”

“…Recently the mineral was described from the weathering zone of the Lubin mine, Lower Silesia, Poland (Kruszewski et al 2020). In general, the formation of rapidcreekite in nature is related to the low-temperature surface processes such as those occurring in hot springs (Roberts et al 1986;Wen et al 2020), weathering zones of ore deposits (Kruszewski et al 2020), karst caves and springs (Onac et al 2013;De Waele et al 2016;D'Angeli et al 2021) and even Arctic glaciers (Lau et al 2017). Rapidcreekite was also found in technological environments, including pyrometal-lurgical slags (Warchulski et al 2015), electrochemical plant sludges (Gaskova et al 2015), cements (Martínez-Ramírez and Fernández-Carrasco 2012;Zhernovsky et al 2016), and mine tailings (Situm et al 2020).…”