b'Pyritethe firestoneFeaturewith the aluminous clay content of the shales, and added wood potash, to give alum.Pyrite provided an essential ingredient, sulphur, for a very dangerous industrial material: gunpowder. In the 13th century the German theologian Albertus Magnus documented gunpowder as a mixture of 2/3 niter (KNO 3from soils and from pigeon and bat droppings in caves of arid regions) and 1/6 each of sulphur and charcoal. The pyrite-derived sulphur functions as an accelerant giving a bigger bang. The modern mix of 74.6% niter, 13.5% charcoal, and 11.9% sulphur gives an even better bang.In the 1500s pyrite featured in the improvement of European weaponry, i.e. the facilitation of carnage wreaked on humans and animals. The hand cannon of the 1300s gave way to the slow, clumsy matchlock musket in the 1400s. The matchlock relied on a lighted match of saltpetre soaked hemp to ignite Figure 6.Pieter Bruegel the Elders 16th century depiction of an alchemist inthe gunpowder charge through a hole in the top of the his laboratory doubtless spurred on in his dead-end endeavours by the recoverymusket barrel. It was cheap and, although hazardous, lasted of gold from pyrite. But this was not transmutation, rather the chemical releaseuntil the 1700s. The projectiles from such weapons were able and concentration of previously invisible gold. Pieter Brueghel the Elder - Theto penetrate the armour of mobile cavalry who could no Alchemist (1558, Ink on paper) Engraved by Philipp Galle / https://commons. longer efficaciously charge the infantry. The wheel lock pistol wikimedia.org/wiki/File:Pieter_Bruegel_the_Elder_-_The_Alchemist.JPG / Publicwith a pyrite sparker ignition was developed for use by the Domain aristocrats of the cavalry to fire at a distance on the ranks of the peasant infantry. It was an elite weapon with an ignition the eye. Crushing and powdering this pyrite (known as pyritesmechanism comprising a sprung, hardened steel, serrated to an alchemist) and then adding mercury causes the gold towheel revolving rapidly against a piece of pyrite which ejected form an amalgam which when heated vapourises the mercurysparks into the powder pan of the weapon (Figure 7). It was and leaves visible gold. So pyrites could be changed to gold,simple, sturdy, reliable, and could be fired in an instant from seemingly corroborating the theory of transmutation andhorseback, but it was expensive so it was mainly used by the boosting hopes of converting base metals into gold if only thecavalry. Pyrite enjoyed a brief moment of military distinction, right conditions could be found. However, they never were.being a key component of a weapon which radically changed Many lives were spent, and fortunes lost, in these doomedRenaissance battle tactics. It was replaced by the flint lock in pursuits. the 1600s.Metamorphosis in the classical sense is the transformation of something into a new form, such as a human being turned into animal, vegetable, or mineral matter. Ancient and medieval cultures were imbued with the idea; it persists to the present day in religion, and fantasy movies. The Roman poet Ovid (43BCAD 17) relates some 250 instances of transformations in his Metamorphoses. The possibilities of transformation/transubstantiation/transmutation encouraged metal workers and many others to try to make precious metals from baser materials. They believed metals grew in the earth from an imperfect to a perfect state. Some expended enormous experimental effort to hasten the process by instantaneous transmutation. Others had a more leisurely approach such as the gold-panning Conquistadors in South America who threw lumps of platinum back into rivers to ripen into gold.Pyriteindustrial chemistryMost sulphide ores require roasting to obtain sulphur dioxide, SO 2 , but pyrite has such a high sulphur content (53.4%) that in a pure and finely divided form it can maintain its own combustionFigure 7.A double barrel wheel lock pistol, beautiful but deadly. This type of without an external heat source. pistol was fast and reliable, but expensive, and was used mainly by European cavalry in the 1500s https://commons.wikimedia.org/wiki/File:Double_For centuries pyrite was the main source of sulphur and sulphurBarrelled_Wheellock_Pistol_MET_2306.jpg / Creative Commons CC0 1.0 dioxide used for bleaching, and in the manufacture of sulphuricUniversal Public Domain Dedication. The wheel lock ignition mechanism is acid, an important industrial chemical. Sulphuric acid appliedshown underneath: when a sprung steel (H7) wheel revolved rapidly against to phosphate rock makes superphosphate for agriculture. In thea piece of (yellow) pyrite, sparks were generated and detonated a gunpowder charge in the pan of a pistol. Prime position of the pyrite is shown on left; fire clothing industries, pyrite produced the potassium aluminiumposition is on the right https://commons.wikimedia.org/wiki/File:Wheellock_sulphate alum indispensible in the chemical fixing of dyes tomechanism_(animated).gif / Creative Commons Attribution-Share Alike 3.0 cloth. One recipe involves pyrite shales where the pyrite reactsUnported57 PREVIEW DECEMBER 2019'