Clinical and Forensic Aspects of the Different Subtypes of Argyria

Argyria encompasses the different cosmetic alterations that can develop if enough silver particles deposit in a specific tissue, typically in the skin, ranging from localized dark-blue macules to a generalized slate-gray/bluish tinge following systemic absorption. This work aims to fully review the state of the art regarding pathophysiology, diagnosis, treatment, and relevant clinical and forensic features of argyria. Argyria has been diagnosed in a wide range of ages, both sexes and varied ethnicities, with no known individual predisposing factors. Ultraviolet radiation with subsequence increases of melanin production aggravates the discoloration due to a reduction in the silver deposits. Physical examination and silver exposure in the anamnesis can be highly suggestive of the diagnosis, but a histopathological analysis with Energy-Dispersive X-ray Spectroscopy is required to unequivocally determine the discoloration etiology. Safe and effective treatment has only been accomplished with laser techniques, though only a few cases have been reported and with limited follow-up time. In conclusion, argyria typically has an occupational or iatrogenic etiology. It should be suspected when a patient presents with typical skin or eye lesions. A seemingly viable treatment modality, with laser technology, is finally within the horizon.

The Lavrion Mines: A Unique Site of Geological and Mineralogical Heritage

The Lavrion area corresponds to the western part of the Attic-Cycladic metamorphic belt, in the back-arc region of the active Hellenic subduction zone. Between the Eocene and the Miocene, metamorphic rocks (mainly marbles and schists) underwent several stages of metamorphism and deformation due to collision and collapse of the Cycladic belt. Exhumation during the Miocene was accommodated by the movement of a large-scale detachment fault system, which also enhanced emplacement of magmatic rocks, leading to the formation of the famous Lavrion silver deposits. The area around the mines shows the stacking of nappes, with ore deposition mainly localized within the marbles, at marble-schist contacts, below, within, or above the detachment. The Lavrion deposit comprises five genetically-related but different styles of mineralization, a feature never observed in another ore deposit elsewhere, containing the highest number of different elements of any known mining district. The local geology, tectonic, and magmatic activity were fundamental factors in determining how and when the mineralization formed. Other key factors, such as the rise and the fall of sea level, which resulted from climate change over the last million years, were also of major importance for the subsequent surface oxidation at Lavrion that created an unmatched diversity of secondary minerals. As a result, the Lavrion deposit contains 638 minerals of which Lavrion is type-locality for 23 of them, which is nearly 12% of all known species. Apart from being famous for its silver exploitation, this mining district contains more minerals than any other district on Earth. The unique geological, mineralogical, and educational (mining, archaeological, and environmental) features suggest that it is highly suitable to be developed as a future UNESCO Global Geopark.

Mineral Deposits of Myanmar (Burma)

Myanmar is richly endowed in natural resources that include tin, tungsten, copper, gold, zinc, lead, nickel, and silver, as well as gemstones. The material covered over a nine-day field trip explores the country’s complex geology, which reflects a collisional history stretching from the Late Triassic to at least Miocene, sited at the eastern end of the India-Asia suture. The country can be divided into three principal metallotects: the Wuntho-Popa magmatic arc, with granites and associated porphyry-type and epithermal Cu-Au mineralization; the Slate Belt (also called the Mogok-Mandalay-Mergui Belt), with multiple precollisional I-type and postcollisional S-type crustal melt granites that host significant tin-tungsten mineralization, and which also are host to a number of orogenic gold deposits; and the Shan Plateau with massive sulfide-type and also MVT-style lead-zinc-silver deposits.

Geochronological and geochemical features of magmatic gold- and silverbearing complexes in the Chukotka sector of the Russian Arctic coast

Research subject. This study was devoted to magmatic complexes in Northwestern Chukotka associated with the largest gold and silver deposits across Kupol’skii (Kupol field) and Ilirnei (Dvoinoe and September fields) ore junctions. Materials and methods. The petrogenic elements of ore-containing igneous rocks were determined using a spectrometer ICAP 6500Duo (USA). An elemental analysis of igneous and ore samples was performed by inductively coupled plasma spectrometry (ICP-MS). The age was determined by zircons (SHRIMP-II, VSEGEI isotope research center, St. Petersburg) using a laser ablation system NWR-213 (USA). Results. New information concerning the dating of magmatic complexes and gold-bearing magmatic systems in the ore junctions under study was obtained. It was established that the manifestations of magmatism in the Kupol and Ilirnei ore junctions differ in terms of the main phase formation age. The age of the Ilirnei ore junction, which is represented by large-volume intrusions of granitoids, leucogranites and volcanites of medium-basic composition, was determined to be 124–114 Ma. The age of mineralization, which is associated with later magmatism phases – small intrusions and a dike complex of predominantly granodiorite composition –, was estimated to be (93– 92) ± 2.0 Ma. In the Kupol ore junction, the magmatism associated with mineralization was dated 91.0 ± 1.4 Ma, while the age of rhyolite dikes containing mineralization was estimated to be 88.9–89.0 Ma.Conclusion. The results of the RMS analysis of the Kupol and Ilirney ore junctions suggest that ore formation in this region was connected with a single stage of activation of deep processes and mantle-crust interaction with participation of deep (mantle) fluids.