Next Article in Journal
Rare Earth and Phosphorus Leaching from a Flotation Tailings of Florida Phosphate Rock
Next Article in Special Issue
Cerromojonite, CuPbBiSe3, from El Dragόn (Bolivia): A New Member of the Bournonite Group
Previous Article in Journal
Supergene Uranyl Mineralization of the Rabejac Deposit, Lodève, France
Previous Article in Special Issue
New Occurrence of Rusinovite, Ca10(Si2O7)3Cl2: Composition, Structure and Raman Data of Rusinovite from Shadil-Khokh Volcano, South Ossetia and Bellerberg Volcano, Germany
Open AccessArticle

Aurihydrargyrumite, a Natural Au6Hg5 Phase from Japan

1
Institute for Solid State Physics, the University of Tokyo, Kashiwa, Chiba 277-8581, Japan
2
Sunagawa cho, Tachikawa, Tokyo 190-0031, Japan
3
Ehime University Museum, Ehime University, Matsuyama, Ehime 790-8577, Japan
*
Author to whom correspondence should be addressed.
Minerals 2018, 8(9), 415; https://doi.org/10.3390/min8090415
Received: 28 August 2018 / Revised: 14 September 2018 / Accepted: 17 September 2018 / Published: 19 September 2018
(This article belongs to the Special Issue New Mineral Species and Their Crystal Structures)
Aurihydrargyrumite, a natural Au6Hg5 phase, was found in Iyoki, Uchiko, Ehime Prefecture, Shikoku Island, Japan. Aurihydrargyrumite with a metallic silver luster occurs as a submicron- to 2 μm-thick layer on the outermost surface of the placer gold. A prismatic face may be formed by {001} and {100} or {110}. The streak is also silver white and its Mohs hardness value is ca. 2.5. Its tenacity is ductile and malleable, and its density, as calculated based on the empirical formula and powder unit-cell data, is 16.86 g·cm−3. The empirical formula of aurihydrargyrumite, on the basis of 11 Au + Hg, is Au5.95Hg5.05. Aurihydrargyrumite is hexagonal, P63/mcm, with the lattice parameters a = 6.9960(10) Å, c = 10.154(2) Å and V = 430.40(15) Å3, which is identical with the synthetic Au6Hg5 phase. The seven strongest lines in the powder X-ray diffraction (XRD) pattern [d in Å(I/I0)(hkl)] were 2.877(29)(112), 2.434(42)(113), 2.337(100)(104), 2.234(87)(211), 1.401(39)(314), 1.301(41)(404), and 1.225(65)(217). Aurihydrargyrumite forms through the weathering of mercury-bearing placer gold by involvement of self-electrorefining. This new mineral has been approved by the IMA-CNMNC (2017-003) and it is named for its composition, being a natural amalgam of gold (Latin: aurum) and mercury (Latin: hydrargyrum). View Full-Text
Keywords: aurihydrargyrumite; Au6Hg5 phase; gold; placer; self-electrorefining; Ehime; Japan aurihydrargyrumite; Au6Hg5 phase; gold; placer; self-electrorefining; Ehime; Japan
Show Figures

Figure 1

MDPI and ACS Style

Nishio-Hamane, D.; Tanaka, T.; Minakawa, T. Aurihydrargyrumite, a Natural Au6Hg5 Phase from Japan. Minerals 2018, 8, 415.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

1
Back to TopTop