Hostname: page-component-586b7cd67f-r5fsc Total loading time: 0 Render date: 2024-11-25T07:15:09.612Z Has data issue: false hasContentIssue false
  • English
  • Français

Silver Plating on Copper, Bronze and Brass

Published online by Cambridge University Press:  21 April 2011

Susan La Niece
Get access Rights & Permissions [Opens in a new window]

Extract

Silver has generally been valued second only to gold from at least as early as 2000BC. A material which is highly prized becomes a status symbol and cheaper imitations find a ready market. Craftsmen very early developed methods of applying thin layers of silver onto base metal as an economical use of precious metal, whether for its decorative effect or, particularly in the case of plated coins, to deceive the customer. Unfortunately, silver plating is less commonly preserved than gold plating, and corrosion at the interface between the silver and base metal may destroy the evidence of how the plating was applied. The situation is complicated because many of the white metal surfaces on pieces labelled as ‘silvered’ are in fact produced by tin, or more rarely, by arsenic. Nevertheless, there are still sufficient surviving examples to indicate that silver plating has a long history during which techniques were developed to give better results and to allow more economical use of the precious metal.

Type
Research Article
Information
The Antiquaries Journal , Volume 70 , Issue 1 , March 1990 , pp. 102 - 114
Copyright
Copyright © The Society of Antiquaries of London 1990

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

1 British Museum, Dept. Western Asiatic Anti- quities 25096, registration no. 1894, 1-16, 3. Barnett, R. D., ‘Some Syrian bronzes’, Brit. Mus. Quart. (1934-1935), pl- XIII, nos. 3–4Google Scholar . Negbi, Ora, Canaanite Gods in Metal (Tel Aviv, 1976), no. 1354, pl. 23Google Scholar.

2 Maryon, H., ‘Soldering and welding in the Bronze and Early Iron Ages’, Technical Studies in the Field of the Fine Arts (Cambridge, Mass. 1938), 75–108Google Scholar . Lang, J. and Hughes, M. J., ‘Joining techniques’, in Oddy, W. A. (ed.) Aspects ofEarly Metallurgy, British Museum Occasional Paper 17 (London, 1970), 169–77Google Scholar . Lang, J. and Hughes, M. J., ‘Soldering Roman silver plate’, Oxford J. Archaeol. 3 (1984), 77–107CrossRefGoogle Scholar.

3 Niece, S. La, ‘Technology of silver plated coin forgeries’, in Archibald, M. and Cowell, M. (eds.), Metallurgy in Numismatics III. Roy. Numis. Soc. Special Publication 23, forthcoming.Google Scholar

4 Campbell, W., Greek and Roman Plated Coins, American Numismatic Society No. 57 (New York, 1933).Google Scholar

5 Hughes, G. B., Antique Sheffield Plate (London, 1970)Google Scholar ; Bradbury, F., A History of Old Sheffield Plate (London, 1912)CrossRefGoogle Scholar ; Veitch, H. N., Sheffield Plate (London, 1908)Google Scholar.

6 Bernareggi, E., ‘Nummi pelliculati, (considerazioni sull' argento suberato della Republica Romana)’ Revista Italiana di Numismatica XIII (1965), 5–31Google Scholar ; Kalsch, E. and Zwicker, U. ‘Untersuchungen uber Plattierungen antiker Munzen mit Hilfe der Mikrosonde’, Mikrochimica Acta [Wien], Suppl. III (1968), 210–20Google Scholar.

7 Campbell, , op. cit. (note 4), 143–4.Google Scholar

8 There are a large number of publications on the subject of ancient silver plated coins including: Thompson, F. C. and Chattergee, A. K., ‘Ancient Greek plated coins’ Nature 168 (1951), 158CrossRefGoogle Scholar ; Dolley, R. H. M., Howell, G. F. and Stride, H. G., ‘A contemporary forgery of a William III crown’, Brit. Numis. J. 27 (1953), 205–10Google Scholar ; Paszthory, E., ‘Zwei kleinmunzen aus Athen’, Schweizer Munzblatter 113 (1979), 1–7Google Scholar ; Balog, P., ‘Plated forgeries of Islamic coins’, Revista (Quademi ticinesi di numis-matica e antichita classiche) (Lugano, 1978), 279–85Google Scholar.

9 Charles, J. A., ‘The first Sheffield plate’, Antiquity 42 (1968), 278–84.CrossRefGoogle Scholar

10 Campbell, , op. cit. (note 4), sections 107–35.Google Scholar

11 Morton, R. and Hallett, M., ‘Close plating: a Black Country silver plating process’, J. Hist. Metallurgy Soc. 23/1 (1989), 41–4.Google Scholar

12 For example, Scott, D. A., ‘Depletion gilding and surface treatment of gold alloys from the Narino area of ancient Colombia,’ J. Hist. Metallurgy Soc. 17/2 (1983), 99–115Google Scholar , and Solar, T. del and Grimwade, M., ‘The art of depletion gilding,’ Aurum 12 (1982), 37–45Google Scholar.

13 Cope, L. H., ‘Surface-silvered ancient coins’, in Hall, E. T. and Metcalf, D. M. (eds.), Methods of Chemical and Metallurgical Investigation of Ancient Coinage, Roy. Numismatic Soc. Special Publication 8 (London, 1972), 261–78.Google Scholar

14 Scott, D. A., ‘Gold and silver alloy coatings over copper: an examination of some artefacts from Ecuador and Columbia’, Archaeometry 28 (1986), 33–50.CrossRefGoogle Scholar

15 Iron cores are less common (or perhaps are less well preserved during long burial) but a number are known, particularly from the Roman period. The solubility of the copper with the iron allows the silver alloy plating to bond to th e iron core. Professor U. Zwicker of Erlangen University, Nurem-berg, is undertaking research in this field.

16 Pers. comm. Forthcoming publication.

17 Cope, L. H., ‘A silvered bronze false antoni-nianus ascribed to the Roman Emperor Gordian III AD 238-244’, Metallurgia (1967), 15–20Google Scholar ; Picon, M. and Guey, J., ‘Monnaies d'argent fourrées fabriquees par trempage’, Bulletin de Société Française de Numismatique 23 (1968), 318–21Google Scholar.

18 Barb, A., ‘Zur antiken Munztechnik’, Numismatische Zeitschrift 23 (1930), 1–8Google Scholar ; Darmstaedter, E., ‘How the Nummi Subaerati were made’. Spink Numis. Circ. 39 (1931), 54Google Scholar . Translated from Mitteilsunger der Bayerischen numismatischen Gesellschaft, 48 (1929), 27–38Google Scholar.

19 Campbell, , op. cit. (note 4), 144.Google Scholar

20 Cope, , op. cit. (note 13), 275–6.Google Scholar

21 Cope, L. H., appendix to ‘An Iranian hoard of forged dirhams’, by Morton, A. H., Numis. Chron. 7th ser., 15 (1975), 154–68.Google Scholar

22 Lins, P. A. and Oddy, W. A., ‘The origins of mercury gilding’, J. Archaeol. Set. 2 (1975), 365–73.CrossRefGoogle Scholar

23 Illustrated in Watson, W., Handbook to the Collections of Early Chinese Antiquities in the British Museum (London) (London, 1963), fig. 20fGoogle Scholar . For details of analysis and examination see Oddy, W. A., Padley, T.G. and Meeks, N. D., ‘Some unusual techniques of gilding in antiquity’, in Proceedings of the 18th International Symposium on Archaeometry and Archaeological Prospection (Bonn, 1979), 230–42Google Scholar.

24 Theophilus, , On Divers Arts, trans. Hawthorne, J. G. and Smith, C. S. (New York, 1979), ch. 36, 110–12.Google Scholar

25 Biringuccio, V., The Pirotechnia, trans. Smith, C. Stanley and Gnudi, M. Teach (New York, 1959), 367Google Scholar . An anonymous early eighteenth-century German workshop recipe book gives a number of recipes for mercury silvering: Der Kunstliche Gold unä Silber Arbeiter (Nuremberg, 1708), 56-9, 136-9 and 145Google Scholar.

26 Metcalfe, D. M. and Merrick, J. M., ‘Studies in the composition of early medieval coins’, Numis. Chron., 7th ser., 7 (1967), 172–5.Google Scholar

27 Mitchener, M. B. and Skinner, A., ‘Contemporary forgeries in English silver coins and their chemical compositions: Henry III to William III”, Numis. Chron. 145 (1985), 209–36.Google Scholar

28 Excavation no. STAA '77 (766) [441]. Ancient Monuments lab. no. 777593. I am grateful to Justine Bayley and Barry Knight of the Ancient Monuments Laboratory for showing me this piece.

29 Kindly lent by Dr Paul Robinson, Curator of Wiltshire Archaeological Society Museum Reg. no. 1987.316.1.

30 Read, C. H., ‘The Waddesden bequest’ (London, 1902), 106, no. 226.Google Scholar

31 For example a small copper pendant with a lion argent rampant on an enamelled background of unknown colour, English probably late thirteenth or fourteenth century, BM registration no. ML A 68, 7-9, 74. Also a gilt copper pendant engraved with a Papal tiara above a shield, the sides filled with foliage decoration, MLA 94, 2-17, 15. The shield may be interpreted as a bend chequy and in chief two keys argent (mercury silvered), possibly Pope Boniface IX (Tomacelli) 1389-1404. Woodward, J., Ecclesiastical Heraldry (London, 1894), 153–61Google Scholar.

32 Kindly lent by Dr Paul Robinson, Curator of Wiltshire Archaeological Society Museum, Devizes. Reg. No. 1984.94. For discussion of the heraldry see Griffiths, N. ‘Medieval pendants from Edington and Sharcott’, Wilts. Archaeol. Natur. Hist. Mag. 8 (1986), 221–3Google Scholar.

33 Museum of London acquisition no. 893/1.2.3. My attention was drawn to these by Suzanne Keene. Analysis done by Justine Bayley, Ancient Monuments Laboratory. To be published in the Museum of London Medieval Finds from Excavations in London series, forthcoming volume on Dress Fittings.

34 Hook, D., Niece, S. La and Cherry, J., ‘A fifteenth-century mercury-silvered buckle from Hillington, Norfolk’, Antiq. J. 68 (1988), 301–5CrossRefGoogle Scholar . The other pieces include a belt chape from Broken Wharf, London (Museum of London no. A2565; Perkins, J.B. Ward ‘Bronze bel t chapes from London’, Antiq. J. 19 (1939), 197–9 note 35, pl. 1CrossRefGoogle Scholar . Also a buckle from Missenden Abbey (Aylesbury Museum, MA 83, 81) and a belt chape from Dinas Powys (National Museum of Wales 1987. IIIH) ( Morgannwg 31 (1987), 86)Google Scholar.

35 Bara, A., ‘Trois objets en argent de la trouvaille de Liège de 1921’, Bull. Musées Royaux d'Art et d'Histoire, 3rd ser., 16 (1944), 83 ffGoogle Scholar . Tait, H. (ed.), Jewellery through 7000 Years (London, 1976), 164, no. 271aGoogle Scholar.

36 BM Medieval and Later Reg. no. 57, 5-23, 2. Ward, F. A. B., Catalogue of European Scientific Instruments (London, 1981), 32, no. 65Google Scholar.

37 Ibid., 74, no. 207.

38 Hessisches Staatsarchiv Marburg, 4331 Nr. 11, pers. comm. Leopold, J. H.. For details of the globe see his book Astronomen Sterne Gerte (Luzern, 1986).Google Scholar

39 Reg. no. BM MLA 1855, 12-1, 3 c. 1540-60 diam. 434mm, made by Nicolo Rugina of Corfu, perhaps made i n Corfu or Venice. Gilt and silvered brass. Ralph Bernal Collection sal e catalogue, Christie's, 5 March-30 April 1855, lot 1227.

40 It mus t be remembered that traces of mercury may be present as the result of polishing with a silver cleaning powder containin g mercury. Vincent Daniels (pers. comm.) has pointed out that Mrs Beeton in the first edition of her book on Household Management (London, 1859, part 21, para. 2316, 995) warned against the use of such polishes. Also mercury may be left as a residue of preparation process for electroplating known as ‘quicking’;Google ScholarThe Canning Handbook on Electroplating, 22nd edition (Birmingham, 1978), 612Google Scholar.

41 Theophilus, , op. cit. (note 24), 184–5. Also see a handbook of recipes first published in 1688,Google ScholarStalker, J. and Parker, G., A Treatise of Japanning and Varnishing (London, 1960), 67Google Scholar , which gives instructions ‘to guild Iron, Brass or Steel with leaf-gold or silver’ by this method.

42 Fishlock, D., Metal Colouring (London, 1962), 146.Google Scholar

4 Lechtman, H., ‘A Precolumbia n technique for electrochemical replacement plating of gold and silver on objects of copper’, J. Metals 31 (1979), 154–60Google Scholar , and ‘New perspectives on Moche metallurgy: techniques of gilding copper at Loma Negra, Northern Peru’, American Antiquity 47/1 (1982), 3–30CrossRefGoogle Scholar.

44 Daniel, L., ‘Monnaies sauces’, Bulletin de la Société Française de Numismatique (1969), 360–2.Google Scholar

45 Cope, , op. cit. (note 13).Google Scholar

46 Carradice, I. and Niece, S. La, ‘The Libyan War and coinage: a new hoard and the evidence of metal analysis’, Numis. Chron. 48 (1988), 33–52.Google Scholar

47 Recipes are given in workshop handbooks, for example ‘to silver-over Brass or Copper, as the clockmakers do their Dial-Plates’, Stalker, and Parker, , op. cit. (note 41), 66–7Google Scholar , first published in 1688. Also The Shop Records of Daniel Bumap, Clockmaker 1759-1838, ed. Hooper, P. R. (Connecticut Hist. Soc, 1958), 126Google Scholar , and the reference under Cold Silvering in Cooley, A. J., Encyclopaedia of Practical Recipes Vol. 11, 6th edition (London, 1880), 1496Google Scholar.

48 Canning Handbook of Electroplating, op. cit. (note 40).

49 For reviews of plating and other metals as well as silver see Linns, P. A., ‘A History of Metal Coatings on Metals pre 1800 AD’, unpublished Masters dissertation, City of London Polytechnic (London, 1974)Google Scholar , and Padley, T. G., ‘Methods of Gilding and Silvering before 1850’, unpublished Masters dissertation, Bradford University (Bradford, 1976)Google Scholar.