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Moissanite (/ ˈ m ɔɪ s ə ˌ n aɪ t /) [5] is naturally occurring silicon carbide and its various crystalline polymorphs.It has the chemical formula SiC and is a rare mineral, discovered by the French chemist Henri Moissan in 1893.
In 1893, Moissan began studying fragments of a meteorite found in Meteor Crater near Diablo Canyon in Arizona. In these fragments he discovered minute quantities of a new mineral and, after extensive research, Moissan concluded that this mineral was made of silicon carbide. In 1905, this mineral was named moissanite, in his honor.
The earliest gold artifacts were discovered at the site of Wadi Qana in the Levant. [13] Silver is estimated to have been discovered in Asia Minor shortly after copper and gold. [14] There is evidence that iron was known from before 5000 BC. [15] The oldest known iron objects used by humans are some beads of meteoric iron, made in Egypt in ...
Reconstruction of Ötzi's copper axe (c. 3300 BCE). The Copper Age, also called the Eneolithic or the Chalcolithic Age, has been traditionally understood as a transitional period between the Neolithic and the Bronze Age, in which a gradual introduction of the metal (native copper) took place, while stone was still the main resource utilized.
Gold, silver and copper were the first to be used by ancient humans. Gold and copper are both found in their 'native' state in nature, and were thus the first to be exploited as they did not need to be smelted from their ores. They could be hammered into sheets or decorative shapes.
Chalcolithic Age (copper age) beginning about 7,000 years ago: copper, gold, silver, mercury. In the early Bronze Age, lead was used with antimony and arsenic. [2] The use of meteoric iron–nickel alloy has been traced as far back as 3500 BC. Iron Age, Ancient Near East (1300–600 BC), India (1200–200 BC), Europe (1200 BC – 400 AD).
Around 1,500 gold objects dating to the Bronze Age survive in collections, around 1000 of them from Ireland and the other 500 from Britain; this is a much smaller number than would have been originally crafted, leading archaeologists to believe that "many thousands of gold objects were made and used" in the Bronze Age British Isles. [1]
The Old Copper Complex of the Western Great Lakes is the best known, and can be dated as far back as 9,500 years ago. [4] [1] Great Lakes natives of the Archaic period located 99% pure copper near Lake Superior, in veins touching the surface and in nuggets from gravel beds.