ABSTRACT

Roasted residues from historic gold mine processing at the Golden Point historic reserve were thoroughly cemented by surfical processes. The cements are composed mainly of oxidised and acidic Fe–As–S minerals with varying particle size and crystallinity. Bukovskyite (Fe₂[AsO₄][SO₄][OH].7H₂O) and scorodite (FeAsO₄.2H₂O) are the most prominent of these minerals, but a range of As and S bearing ferric iron oxyhydroxide compounds are also abundant, including K-jarosite and schwertmannite. Arsenolite (As₂O₃) is a minor component, either persisting from original roasting or precipitated via local reduction in the cement. After the historic roasting the residues were treated with liquid Hg to extract gold, and some of that Hg remains in the residues. This Hg now occurs as microcrystalline schuetteite (Hg₃[SO₄]O₂), remobilised nano-scale liquid Hg droplets, and as micron-scale Hg-rich layers in ferric iron oxyhydroxide compounds in the cements. Tungsten mobilised from primary ore scheelite is contained in ferric iron oxyhydroxide and as Fe-meymacite (WO₃.xFe₂O₃.nH₂O) in the cements. The cementation processes have effectively confined metals within the residues.

摘要

在金点历史保护区的历史性金矿加工过程中产生的烘烤残留物通过冲浪过程得到了彻底的胶合。水泥主要由氧化和酸性的Fe-As-S矿物组成，具有不同的粒径和结晶度。Bukovskyite（FE ₂ [ASO ₄ ] [SO ₄ ] [OH]·7H ₂ O）和臭葱石（FeAsO ₄ ·2H ₂ O）是最突出的这些矿物质，但范围作为与S轴承三价铁羟基氧化铁化合物也丰富，包括钾黄铁矿和schwertmannite。Arsenolite（As ₂ O ₃）是次要成分，要么因原始焙烧而持续存在，要么因水泥的局部还原而沉淀。经过历史性的焙烧后，将残留物用液态汞处理，以提取金，其中一些汞残留在残留物中。现在，这种Hg以微晶菱锰矿（Hg ₃ [SO ₄ ] O ₂），重新固定的纳米级液态Hg小滴形式出现，并且在水泥中的羟基氧化铁铁化合物中以微米级富Hg形式出现。从原矿白钨矿中迁移出来的钨被包含在三氧化二铁中，并作为水泥中的铁-memmacite（WO ₃ .xFe ₂ O ₃ .nH ₂ O）。胶结过程已将金属有效地限制在残留物中。