I have mentioned these things precisely because they are very little known by the general public and even by those who are supposed to be professionals in such domains. Because of this, references are scarce.
References about the platinum technology in South America before the arrival of the Europeans:
"Ancient Platinum Technology in South America, its use by the indians in pre-hispanic times", by David A. Scott and Warwick Bray, Institute of Archaeology, University of London, 1980.
"Metallurgy of Gold and Platinum among the Pre-Columbian Indians", Nature, 1936.
About the knowledge of the natural osmium-iridium alloy in the ancient Mediterranean world, there are several archaeology articles with chemical analyses of Egyptian gold artifacts, most of which contain as inclusions small nuggets of osmium-iridium alloy, whose cause is the fact that the gold was collected from river deposits, where the gold nuggets and the Os-Ir nuggets accumulate together, so when the gold was melted it incorporated the Os-Ir nuggets. (For instance: "The analysis of platinum-group element inclusions in gold antiquities", N.D. Meeksa, M.S. Titea, a British Museum Research Laboratory, London WC1B 3DG, England)
These archaeological finds match perfectly the description of adamant from Plato (in "Timaeus" and in "The Statesman"), where adamant is described as the "knot of gold", which is found together with gold, but it cannot be shaped like gold, because it is too hard and impossible to melt. The same description of adamant is provided by Pliny the Elder in his tenth book, which adds besides it the description of the Indian adamants, which are completely different from the classical adamant, being octahedral crystals, not metal nuggets, which matches what are now called diamonds.
The earliest reference to "adamant" is at Hesiod, who describes how Gaia has made a sickle blade from "grey adamant", for the castration of Uranus, which makes no sense as a reference to modern diamonds, which are neither grey nor suitable to be forged into a blade, but it makes perfect sense as a reference to the grey Os-Ir alloy, the hardest metal known to Hesiod, which humans were too weak to forge, but surely a huge goddess like Gaia should be able to forge. Other references to Os-Ir adamant are in Aeschylus (Prometheus is bound with chains made of adamant; another use that makes perfect sense for a metal, but which would be impossible for fragile diamond crystals, which cannot be forged into chain links) and in Theophrastus.
There are a few other articles about the history of platinum and platinum-group metals that have relevant information about all these things, but I do not remember now the titles or authors.
The fact that by searching the Internet you can find a lot of incomplete or even completely incorrect information about many things proves that one should never trust the answers given by an LLM for any really important question, because an LLM will provide the information most likely to be found in its training sources, while truth cannot be based on democracy. On the contrary, much too frequently the majority opinion is more likely to be incorrect, than the minority opinion.
