1 8 A D V A N C E D M A T E R I A L S & P R O C E S S E S | A P R I L 2 0 2 2 by a conduit through which the flange passed while the coin was pressed in its edge, raising it and creating its pre-listel and eliminating the burrs left by the cut of the coin. Afterward, the coin was annealed to soften it, eliminating internal tensions. The annealing of the blanks was followed by washing to eliminate any rust formed during annealing. They were washed first in a chemical solution and then with a bath of soap and water that left its surface shiny. The coins were dried initially on trays with hot sawdust, and years later in drying machines[4]. SUMMARY Chile in the 1850s, as a growing nation, adopted emblems and symbols in line with new concepts of freedom, union, force, and independence. One way the country demonstrated these new images was in its currency, with a law passed in 1851 directing the minting of copper coins. Two Chilean copper coins from this time period were studied. Knowing these coins were virtually pure copper, electrolytic cleaning using sodium hydroxide was used to clean them, though it is not recommended for copper alloys and silver alloys. All the products of corrosion (greenish layer of malachite) were separated in around 60 minutes. The entire surface could be seen and studied in detail. In addition, the good state of preservation of these ancient coins was verified. Coin-collector catalogs verified that the currencies are legitimate and confirmed where and how the coins were minted. ~AM&P For more information: Patricia S. Carrizo, chemical engineering and archaeometallurgy specialist, National Technological University, Argentina, patricia.carrizo@frm.htn.edu.ar. References 1. A. Aldaz, et al., A Simple Tool for the Electrolytic Restoration of Archaeological Metallic Objects with Localized Corrosion, Studies in Conservation, Vol 31, 1986. 2. C.E. Birchenall and R.A. Meussner, Principles of Gaseous Reduction of Corrosion Products, National Bureau of Standards Special Publication, No 479, p 39-57, 1977. 3. Images used for comparison: First type: courtesy of Classical Numismatic Group St. James’s Auctions LLC and Second type: courtesy of Heritage Auctions (www.ha.com). 4. B. Muñiz García, Fabricación de la moneda a través de los tiempos (Manu- facture of Coins through the Ages), Revised version October 2005-2008. GET ENGAGED, GET INVOLVED, GET CONNECTED The ASM Online Community on ASM Connect, at connect.asminternational.org, is a platform where experts and knowledge seekers can connect and communicate. ASM Members can get the ball rolling by posting questions and information briefs about technical areas of interest. For topics of sustained interest, dedicated communities can form; these can evolve into ASM technical committees if the members wish to collaborate on projects for the benefit of the ASM community. The ASM Archaeometallurgy Committee was recently launched and ASM members with interest and experience in the study and characterization of historic metals and artifacts are welcome to join. A planned special issue of the International Metallographic Society journal Metallography, Microstructure, and Analysis is just one of the projects underway. For more information, contact committee chair Patricia Silvana Carrizo or staff liaison Scott Henry, scott.henry@asminternational.org. HEATON’S MINT An interesting part of this study was the research done into the history of where and how the coins were made. Because they were minted in England, news stories and other documentation are available to tell a fuller story. Ralph Heaton II (1794–1862) was the son of Ralph Heaton I, an engineer, inventor, and businessman in England. Ralph Heaton II was a die sinker operating independently of his father. In December 1817 Ralph I conveyed to his son land and buildings to enable him to develop a separate company. Ralph II engaged in brass founding, stamping, and piercing. Brass chandeliers were made for the newly invented gas lighting and he patented a “bats wing” burner. At an auction In April 1850, Ralph Heaton II bought four steam screw presses and six plate presses for making blanks from metal strapping from the defunct Soho Mint, created by Matthew Boulton around 1788. A newspaper of the time also reported that the complete set of presses, pneumatic pumps, and other machinery for minting, were acquired by Ralph Heaton and Son, with the intention to take over Soho’s contracts. Unlike the government-owned Royal Mint, Heaton was able to get permission to produce coins for foreign powers. In 1851 Heaton and Son began producing currency for other nations including Chile, as well as minting coins outsourced by the Royal Mint.
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