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Corrosion and Oxidation of Metals and Alloys
Published in Yip-Wah Chung, Monica Kapoor, Introduction to Materials Science and Engineering, 2022
One unpleasant household chore is to clean off the tarnish on silverware. The usual method is to use a soft cloth to rub and buff the silverware. That takes muscle and patience. Fortunately, there is a better way (Figure 8.1). Take a quart of warm water. Dissolve into it one tablespoon of washing soda and one tablespoon of salt. Lay a sheet of aluminum foil at the bottom of the water container. Now, here is the magic: immerse the silverware into the water, and make sure that it is in contact with the aluminum foil. In seconds, the tarnish is gone. Remove the silverware. Rinse in tap water and dry, and it’s done!
Metal Manufacturing Processes and Energy Systems
Published in Swapan Kumar Dutta, Jitendra Saxena, Binoy Krishna Choudhury, Energy Efficiency and Conservation in Metal Industries, 2023
Swapan Kumar Dutta, Binoy Krishna Choudhury
Silver is the most electrical and thermal conductive metal. In 99.999% pure form, silver is used as silver paint or paste in printed circuit boards, electronics and solar photovoltaic junctions. Sterling silver (92.5% pure) is used as jewelry, silverware and other goods. Silver is weighed in troy ounces, one unit of which is equal to 31 gm or 0.031 kg; or in ounces, one unit of which is 28 gm or 0.028 kg.
The Pewterer and the Chymist: Major Erasmus Purling and his Refined Tin
Published in Ambix, 2022
On the fifteenth of June, 1659, Purling was granted another privilege whose text can be found among the archives of the Paris cour des monnaies (where his claims were ultimately acknowledged) and also in the National Archives of the UK at Kew.62 Its terms and conditions, including the thirty-year duration, were quite similar to the terms of 1657. What differed were the justifications provided to back the grant, which were more elaborate than in the 1657 abridged version. The text celebrated “the good & pleasant services rendered by the said Purling to the late King, our most honoured Lord & Father [Louis XIII], & to Us [Louis XIV], on various perilous occasions where he generously exposed his life as an Engineer.” The preamble of the privilege also emphasised, in a Baconian and mercantilist style, the usefulness of Purling’s scheme: The growth of Kingdoms coming partly from the increase of the trade which is made there & from the establishment of various manufactures that the rare men invent by the force of their spirit, which discovers every day new secrets in Nature […]. For this reason we have listened favourably to the proposal made to us by Erasmus Purling, one of our ordinary engineers, to establish in our kingdom the manufacture and sale of a new material, which he composes from a pure substance that he takes from tin, which is so clean, so fixed & so little porous, that it approaches the goodness, the lustre, the sound, the hardness, the weight & the volume of Silver of which one will be able to easily manufacture all kinds of Tableware & the innocent trade that will ensue will be of great use to our subjects and will bring considerable relief to many people of different conditions, who will not be satisfied with ordinary pewter, and will be well-off, not being able to have Silverware without being inconvenienced, to find at a mediocre price some new material which holds the middle between Pewter & Silver, which is more beautiful inside than outside & which will be better & more resembling to the Silver at the last day of its service than its first.The privilege, which undoubtedly repeated the phrasing of Purling’s petition, thus deflated some of the attacks contrived in La clef du cabinet, namely the superficial quality and poor durability of his metal. The end of the privilege also offered a description of Purling’s trademark, a crowned fleur-de-lys framed by the letters “E” and “P” and by a crowned moon, undoubtedly alluding to the silver-like quality of the metal. The punch was to be cut by an engraver from the Parisian Mint and then kept, engraved in a copper table, in the registry of the court des monnaies.63