SILVER - C&EN Global Enterprise (ACS Publications)

I WAS FIRST DRAWN TO THE MAGIC OF SILver's luster while standing as a child in the British Museum, gazing at a finely polished metallic silver mirror ...
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IT'S ELEMENTAL! The relationship between silver and the history of humankind has endured. Silver has a number of unique properties that set it apart from other metals. These include strength, malleability and ductility; electriALAN SHAW, CODEXIS cal and thermal conductivity; and, as already began through admiration of Greek and referenced, high reflectance of light and a WAS FIRST DRAWN TO THE MAGIC OF SILver's luster while standing as a child in Roman artifacts, but it certainly did not lesser known but increasingly important the British Museum, gazing at a finely end there. My love of all things ancient re- medical application as a bactericide. History reflects man's almost lustpolished metallic silver mirror ful quest to acquire silver, and our and asking, "Why?" Not having modern vocabulary is replete with the benefit, at the time, of a college references to it. Indeed, over the education and a second degree mayears, silver, like no other metal, has joring in transition-metal chemistry become synonymous with beauty, the question went unanswered. wealth, style, health, and mystique. Today however, silver's time-honFor example, the phrase "born with ored and unique ability to reflect ala silver spoon in your mouth" is a refmost 100% of the light that falls on erence to wealth and health. In the it is, for me, more easily explained. 18th century, babies who were fed It's a result ofteamwork between light with silver spoons were found to be and the outermost single electron. healthier than those fed with spoons This electron, when activated by made from other metals, and silver light, absorbs energy that enables it to jump into ahigher, faster orbit around IN HIS IMAGE Alexander the Great minted silver pacifiers have subsequently found wide use in the U.S. because of their the atomic nucleus. This new orbit coins emblazoned with his image. beneficial health effects. cannot, however, be permanently susTo ask for silver service would be to extained—the attraction ofthe nucleus is too vealed, after years of study a fundamental, great. As the electron falls back to its origi- almost deific, relationship between man pect the very best. Tofindoneself looking and this indispensable metal that has per- for a silver lining is to hope for a benevolent petuated into modern times, albeit in a outcome to an otherwise uncomfortable SILVERATAGLANCE and adverse situation. A star of the silver more subtle form. Name: From the Anglo-Saxon seolfor, The Druids of the ancient British Isles screen is in part a reference to the use of silsilver. The symbol is from the Latin harvestedholy misdetoe and oakleaves with ver in thefilmindustry but also, again, a reword for silver, argentum. finely engraved and enchanted silver sickles. flection of its association with beauty and Atomic mass: 107.87. The very shape of these swords is reflective style. Even in nature, the silver birch is reHistory: Known since ancient times. ofthe image ofthe crescent moon, the heav- garded as a tree of elegance, commonly reAncient slag dumps indicate that silver enly body silver was believed to represent ferred to in northern Europe as the "Queen was separated from lead as early as on Earth. Alexander the Great, a devotee of the Forest." of the Olympian Pantheon, believing himFinally if you were a lycanthrope or in3000 B.C. self to be a god in life, was after deed a vampire, according to Occurrence: Silver occurs in ores indeath worshiped in association myth, to be struck by a silvercluding argentite and horn silver and in with the sun god Helios. Was tipped arrow or bullet would reconjunction with deposits of ores conthere a connection between this taining lead, copper, and gold. sult in instant and irrevocable cult and the gifting ofhighly polAppearance: White metallic solid. death. For me, the great author ished and quite valuable silver Behavior: Silver has the highest electriJ. R. R. Tolkien so eloquently shields to Alexander's most seacal and thermal conductivity of all metals captured all of the aforemensoned veterans, the Hypaspists, and possesses the lowest contact resisttioned characteristics when dean elite group within the Agema THIS ELEMENT ance. It is very ductile and malleable. scribing the Mirror of Galadriel ' BROUGHT; :; (royal guards)? This group came Uses: Used to make photographic film, in the epic trilogy "Lord of the to You BV}. to be known as the Agryaspids, tooth filings, silverware, mirrors, batterRings." CODEXIS or Silver Shields, and became as ies, photosensitive glass, and as an We end as we began, with a refamous as Caesar's 10th Legion electrical conductor. Silver iodide is flection of man and his endless or Napoleon's Old Guard are to us now used for seeding clouds to produce rain. interaction with this most noble ofmetals. One can visualize the scene as an enemy For me, silver represents true majesty nal orbit, its absorbed energy is radiated out- column advanced toward the Macedonian among the elements. If gold claims to be ward in the form of light, resulting in the line, when, on Alexander's command, the its king, silver must surely be its queen. eye-pleasing radiance known as luster. shields and the full power of the sun's rays l b the ancients, however, silver was an were brought to bear. It is not hard for me Alan Shaw ispresident and chief executive offiobject of wondrous beauty, imbued with to imagine Alexander claiming the au- cer ofCodexis. He has hada long career in the fine the mystic qualities of the moon, whose thority and divinity of the sun at such a chemicals industry, including with Clariant, dark and mysterious nature it seemed to time—hence, perhaps, his association with Archimica (BTPplc), Chirotech Technology Ltd., mirror. My personal fascination with silver it after life. andlCI.

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