In this contribution we discuss a series of porphyry and porphyry-skarn mineral systems, which constitute important metallogenic belts along major lithospheric breaks and/or collision zones that form the margins of the North China craton and the Yangtze craton. We describe a selection of porphyry and porphyry-skarn deposits in the Great Xing’an Range in northeast China, the Yanshan-Liaoning, Xilamulum belts along the northern margin of the North China craton, the Qinling orogen, and the Middle-Lower Yangtze River Valley along the bonudaries between the North China and the Yangtze cratons. The occurrence of platform carbonate successions may have played some role in the evolution of ore fluids that resulted in the formation of porphyry-skarn deposits. The porphyry deposits of eastern China, although sharing some common features with classic porphyry systems that are related to convergent margins, do exhibit unusual features, particularly in terms of ore fluid compositions, the common presence of fluorite, hydrothermal alteration assemblages, which tend to be less hydrous than the porphyry at convergent margins. On the other hand, the porphyry mineral systems of eastern China have some similarities with the Climax-type porphyry. A major tectonothermal event (Yanshanian), which took place in the Jurassic-Cretaceous, affected eastern China and most of the eastern margin of Asia. This Yanshanian event was responsible for the magmatism and associated mineral systems in the region. The granitoid intrusions and accompanying porphyry and porphyry-skarn deposits were developed along orogenic belts and major structural discontinuities mostly along the tectonic boundaries between the North China and Yangtze cratons and between the northern margin of the North China craton and the Mongolia-Siberia plate. The porphyry and porphyry-skarn deposits herein described include: Chalukou in the Great Xing’an Range orogen, Jiguanshan in the Xilamulun metallogenic belt, Xiaojiayingzi, Lanjiagou, Chehugou, Yuanbaoshan in the Yanshan-Liaoning belt, Nanninhu, Yuchiling, Jinduicheng, Lemeingou in the East Qinling orogen, Tongchakoou, Shaxi from the Middle-Lower-Yangtze River Valley. The role of mantle-lithosphere dynamics in eastern China, which led to the formation of these porphyry and porphyry-skarn mineral systems, is discussed and reviewed.

High-resolution images of Mars from National Aeronautics and Space Administration (NASA) rovers revealed mm-size loose haematite spherulitic deposits (nicknamed “blueberries”) similar to terrestrial iron-ooids, for which both abiotic and biotic genetic hypotheses have been proposed. Understanding the formation mechanism of these haematite spherules can thus improve our knowledge on the possible geologic evolution and links to life development on Mars. Here, we show that shape, size, fabric and mineralogical composition of the Martian spherules share similarities with corresponding iron spherules currently forming on the Earth over an active submarine hydrothermal system located off Panarea Island (Aeolian Islands, Mediterranean Sea). Hydrothermal fluids associated with volcanic activity enable these terrestrial spheroidal grains to form and grow. The recent exceptional discovery of a still working iron-ooid source on the Earth provides indications that past hydrothermal activity on the Red Planet is a possible scenario to be considered as the cause of formation of these enigmatic iron grains.

Ulug-Sair Au-Bi-Te-Se mineralization is one prospect for native Au in the Western Tuva, and its origin remains debated. Mineralization consists of gold–sulfide–quartz veins in the host sedimentary rocks (conglomerates, siltstones, shales), quartz–tourmaline, and quartz–carbonate–sericite–altered rocks. To determine its origin, we examined the mineralogical–geochemical features, formation conditions, and fluid sources of the Ulug-Sair ore. A mineralogical–geochemical investigation outlines two substages with Au: an early gold–sulfide–quartz with pyrite, chalcopyrite, galena, gold, and electrum; and a late gold–telluride–sulfide–quartz, characterized by the presence of Bi-bearing minerals (AgBiTe, Bi₂Te₂Se, Cu₃BiS₃, Bi), tellurides (Au and Ag), Se-tellurides (Ag and Bi), and selenides (Au, Ag, and Hg). The paragenesis of Au–Ag tellurides, and fluid inclusion study data (microthermometry, Raman spectroscopy, LA-ICP-MS, and crush leach analysis (gas and ion chromatography, ICP-MS) in quartz showed that quartz–tourmaline-altered rocks were formed by an aqueous Mg–Na–K-chloride fluid with a salinity of 8–10 wt % NaCl eq. at 325–370 °C, whereas the host quartz–carbonate–sericite-altered rocks were formed from CO₂–H₂O fluid containing CH₄ and N₂, with a salinity of 0.18–6.1 wt % NaCl eq. at 200–400 °C. Gold-bearing mineral assemblages were formed at P ~ 0.75–1.0 kbar (~2.3–3 km) due to CO₂–H₂O chloride (Na–K ± Fe, Mg) fluid with CH₄, Na₂SO₄, and Na₂B₂O₅, and salinities 1.7–12.5 wt % NaCl eq. at temperatures decreasing from 360 up to 115 °C (gold–sulfide–quartz veins—360–130 °C, and gold–telluride–sulfide–quartz veins—330–115 °C), and variable fO₂, fS₂, fSe₂, and fTe₂. Results of the investigation of the isotope composition of S in pyrites indicates the magmatic origin of the fluid (δ¹⁸S_{${\mathrm{H}}_2\mathrm{S}$} fluid from −0.4 to +2.5‰). The stable O isotope data in quartz indicates that, at an early substage, the formation of ore involved a fluid of magmatic and metamorphic origin (from +8.2 to +11.6‰), and, in the later substage, multiple sources of hydrothermal fluids (from +3.1 to +10.4‰), including magmatic-derived, metamorphic-derived, and meteoric waters. These data, in conjunction with structurally controlled mineralization, point towards similarities of the Ulug-Sair ore system with orogenic gold deposits.