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History of the Design of Small Weapons
Published in Jose Martin Herrera Ramirez, Luis Adrian Zuñiga Aviles, Designing Small Weapons, 2022
Jose Martin Herrera Ramirez, Luis Adrian Zuñiga Aviles
Native copper was the first metal used by humans [35]. However, this metal in its pure form is fairly soft. Arsenical bronze, an apparently accidental alloy made of copper (Cu) and arsenic (As), was used to obtain useful forms. Considering the Cu-As phase diagram and depending on the As content, the melting point of arsenical bronzes was above 600°C [36]. This means that in ancient times man was able to reach such temperatures to manufacture different weapons such as spears, axes, arrows, bows, swords, knives, and maces. Nowadays, bronze is an alloy of copper and other elements, including tin, aluminum, silicon, and nickel [37]. Considering a bronze made of copper (Cu) and tin (Sn), and according to the Cu-Sn phase diagram [36], the melting point of bronzes may vary from 830°C to 1020°C.
Occurrence and Resources of Magnesium
Published in Hussein K. Abdel-Aal, Magnesium, 2019
Metal ores normally include oxides, sulfides, and silicates. Others are known as native metals (such as native copper). They are not commonly concentrated in the earth’s crust. On the other hand, noble metals (not usually forming compounds) such as gold are found in the earth’s crust. Processing the ores is a must in order to extract the metals contained in these ores from the waste rock. An ore deposit designates an occurrence of a particular ore type. Most ore deposits are named after their location.
The native metals
Published in R. F. Tylecote, The Prehistory of Metallurgy in the British Isles, 2017
Native copper has been found in Cornwall, Scotland, and Ireland.37 it can be of extremely high purity as shown in Table 4, but in an increasing number of cases very high arsenic contents have been found (arsenic is probably present in native form) and it is not possible to say that because a copper object is of very high purity it must have a native origin. Apart from arsenic, the major impurities are iron and silicon which are probably mainly present as Fe(OH)3, and silica, as in native gold.
A geometallurgical study of flotation performance in supergene and hypogene zones of Sungun copper deposit
Published in Mineral Processing and Extractive Metallurgy, 2021
Ataallah Bahrami, Yosef Ghorbani, Jafar Abdollahi Sharif, Fatemeh Kazemi, Morteza Abdollahi, Abbas Salahshur, Abolfazl Danesh
Minerals such as goethite, hematite, limonite, jarosite, malachite and azurite are present in the oxidised and leached zone. In supergene and hypogene zones, sulfide minerals include pyrite, molybdenite, galena, sphalerite, marcasite, pyrrhotite, and copper sulfides (chalcopyrite, bornite, chalcocite, and covellite) with different paragenesis (Alavi et al. 2014). Kaolinite is present in both supergene and hypogene zones, and also native copper and cuprite are also observed between leached and supergene zones. Chemical factors such as pH and Eh and the mineralogy of the host rock are the most important determinants in the emergence of supergene and hypogene minerals. Parameters such as the low percentage of chalcopyrite in hypogene in weathered parts, cold climate of the area and the presence of faults and fracture zones and very deep valleys made the Supergene Sulfide zone in Sungun not be thick and rich, and both zones contain copper oxidised minerals (Kalagari 1999).
Alteration and structural features mapping in Kacho-Mesqal zone, Central Iran using ASTER remote sensing data for porphyry copper exploration
Published in International Journal of Image and Data Fusion, 2021
Soheyla Beygi, Irina Vladimirovna Talovina, Meisam Tadayon, Amin Beiranvand Pour
During field survey, 14 stations were selected for detailed field checking and sampling (see Figures 8 and 9 for their spatial locations; Table 2). The spatial distribution of the identified hydrothermally altered rocks was verified through GPS surveying and rock sampling. Field photographs of the hydrothermally altered rocks and representative thin and polish sections provided for collected samples from 14 stations are presented in Figures 10 to 12. Station 1 and 2 are located within andesite and andesitic basalt rocks with alterations composed of chlorite, epidote and quartz as main constituents with accessory minerals such as malachite and azurite (Figure 10(a, b)). These minerals are indicators of a propylitic alteration zone (Figure 10(c)), which developed around andesitic rocks. Epidote with a simple mineralisation, including chalcopyrite, pyrite, and a small amount of covellite is the most abundant alteration mineral in this part (Figure 10(d)). Petrographic and mineralogical studies at station 3 show that mineralisation occurs in the argillic alteration zone within andesitic basalt and tuff breccia (Figure 10(e)). The most important primary minerals at this station are native copper, chalcocite, chalcopyrite, bornite and covellite (Figure 10(f)), furthermore the secondary minerals such as azurite and malachite can be found.
Gravity and magnetic data processing further constrained inversion for 3D modelling and tonnage calculation
Published in Applied Earth Science, 2020
Saâd Soulaimani, Saïd Chakiri, Ahmed Manar, Ayoub Soulaimani, Abdelhalim Miftah, Mustapha Boujamaoui
Jarni et al. (2015) mentioned that the geological data analysis shows that the Hajjar deposit is a polymetallic volcanogenic massive sulphide ore deposit, with ore resources of 18 million tonnes with 4–10% zinc, 2–4% lead, 0.4–0.8% copper and 60 ppm silver. The sulphide cluster has a dominant pyrrhotite grained texture (90–95%) mineralised with sphalerite, chalcopyrite, native copper and silver galena. This orebody is elongated NNW-SSE, with a 250–500 m longitudinal extension, a 50–250 m lateral extension and a thickness of 40–70 m (Figure 2). The mineralisation is hosted in Carboniferous volcanic, volcano-sedimentary formations. It is located immediately on the rhyolitic dome roof, with clear alteration zones. The orebody is covered by an iron cap, which has a very rich cementation zone of native copper (40%) and of lead with a silver galena vein of 10–20 cm (Jarni et al. 2015).