ASM International’s Post

Happy to share a new paper on ore microstructure and microchemistry, recently accepted in American Mineralogist: https://lnkd.in/dddY3rHX Few words about this study: ➡ Evaluating, quantifying and mapping microstructures and microchemistry are important to understand processes of ore and sulfide formation in undeformed and deformed geological environment. In sulfides, it is not an easy task because microstructures are generally not clearly visible with classical microscopic tools. ➡ In our last study, we promote the use of EBSD coupled to u-LIBS mapping to comprehend and compare processes of ore formation at orogen/metallogenic belt scale in seven Pb-Zn(-Ge) deposits from the Pyrenees and Montagne Noire. ➡ More specifically, Electron backscatter diffraction (EBSD) mapping technique gives insightful microstructural evidences on primary sphalerite formation or late sphalerite reworking. This technique should be conventionally used, coupled with microchemical study, to evaluate primary ore formation conditions or late deformation imprint on ore (quantification of misorientation, grain size and shape, etc.). Thanks to all my co-authors and reviewers (especially Alan Boyle).

✨ Special Issue Paper✨ Welcome to read the 5th publications in the following Special Issue "Corrosion Studies on Metallic Cultural Heritage"! If you are interested in contributing to this topic, please submit your abstract here: https://lnkd.in/gn-iqKZ3 or contact our Guest Editors. This Topic is edited by Dr. Blanca Ramirez Barat and Dr. Cristina Chiavari. 📝Title: Early Stages of Metal Corrosion in Coastal Archaeological Sites: Effects of Chemical Composition in Silver and Copper Alloys Authored by Dr. Francesca Boccaccini and Dr. Changguo Chen et.al. Link: https://lnkd.in/g_YFG_Dz Keywords: #silver #alloys;  #copper alloys;  #alloying elements;  #corrosion products;  #burial treatment

Hurry Up!! Till August 30th you have the opportunity to send your Abstract!! Topic ARCHAEOMETALLURGY, is the 2° Special Issue together with Metallography, Microstructure and Analysis Journal

Highlighted at x150,000 magnification, this TEM observation reveals the detailed tubular structure of a 45nm-wide chrysotile fibre naturally occurring in a rock sample from a #nickel #mine. In the geological context of Australia, differentiating #asbestos from other fibrous minerals, organic fibres, and polymorphs already poses a notable challenge, which is further accentuated when the structure is at nanometer-scale dimensions. Accurate detection becomes crucial, hence the significance of using high-resolution electron microscopes for comprehensive geological analysis. #analysis #occupationalhygiene #fibre #electronmicroscopy

Reverse Engineering of Ancient Metals https://a.co/d/07Xqu0e2

American Mineralogist: Compressibility and pressure-induced structural evolution of kokchetavite, hexagonal polymorph of KAlSi3O8, by single-crystal X-ray diffraction https://lnkd.in/gvty-DY4 Kokchetavite (KAlSi3O8, IMA-2004-011) was earlier identified as mineral inclusions in a wide range of crustal rocks and massifs, including those with an ultra-high pressure origin. However, their crystal structures were only guessed on the basis of powder X-ray diffraction patterns. The absence of data on the high-pressure stability and equation of state of this mineral was problematic for people involved in the study of metamorphic crustal complexes. In this work, Romanenko et al. present results of room-temperature compression and observations of pressure-induced structure transitions of kokchetavite up to 11.8 GPa by in situ, single-crystal, synchrotron X-ray diffraction. Observational data provide important information for the identification and interpretation of this phase in mineral inclusions. The authors demonstrate the high structural stability of kokchetavite, therefore, it can be taken into account in thermodynamic modeling of the composition of the fluid-saturated crust.

Petrography (tutorial 1) (part Microscopic description of minerals)

🌟 A Tentative Model for the Origin of A-Type Granitoids 🌟 👉 Highlights: ◽      A tentative conceptual model is presented for the origin of the controversial type of granitoid intrusives known as A-type granites, using the Mesoproterozoic granites of the Danish island of Bornholm as an example. ◽      As typical for A-type granites, these are ferroan and potassic granites highly enriched in many incompatible trace elements, plotting as A-type and within-plate type in tectonic discrimination diagrams. ◽     In the proposed model, underplated mantle-derived basaltic magma may develop into intermediate and siliceous A-type magma through a combination of fractional crystallization with cumulate formation, and partial melting and crustal assimilation, melting itself upwards in a process akin to zone refining in metallurgy. ◽      In relation to the source-based I-, S- and M-type division of granites, A-type magmas may be considered a mixture of highly fractionated I- (igneous source) and M- (mantle source) magmas. ◽      A key factor may be a relatively stable tectonic environment (post-collisional, anorogenic, or extensional), where there is little or no replenishment of more primitive basaltic magma to the system, allowing it to attain more evolved, enriched and extreme compositions. 📜 ✍ Ake. Johansson 📜 Read/Download paper at 👉 https://lnkd.in/dVR84sYD 🏫 Swedish Museum of Natural History Follow 👉 Minerals MDPI ⚒ #minerals #editorschoice #article #openaccess #mdpi

structural defects in the crystal lattice of pink diamond This article relates to Type II Golconda pink diamonds especially of Golconda mines with cubic structure. The defect that is visible in such pink diamond is an extra line that is found to each cubic structure may be towards y axis parallel to the cubic structure of unit cell may be said by crystallographers as X axis or y axis. The crystallography subject is so tough that the position holders in IUCr says that while all say that if anybody can define a crystal (gem) then they can only be crystallographers. Astonishingly, crystallographer say we also can't. the confusion among crystallographer is on such a height that they are confused by admitting " It would be bit embarrassing that gases turn out to be crystals" meaning thereby they discard the theory of gem formation by molten magma. Such is a confusion that is prevailing among the highly specialized scientist of gems (crystals) working in International organisation of IUCr. so how can a Graduate Gemologist completing its short term diploma in four and a half month with or without science subject can identify a gem with simple 10 X eye glass or microscope.

The 2023 blogpost countdown continues. Our 4th most read blogpost of 2023 was 'The History of Neodymium Magnets' #magnets #blogpost #digitalmarketing https://lnkd.in/dKzThZtJ