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Volume 24 No. 6. April 1995 The Journal of Gemmology The Gemmological Association and Gem Testing Laboratory of Great Britain President E.M. Bruton Vice-Presidents A.E. Farn, D.G. Kent, RK. Mitchell Honorary Fellows R.T. Liddicoat Jn1'., E. Miles, K. Nassau, E.!\. Thomson Honorary Life Members D.J. Callaghan, E.A. Jobbins Council of Management CR Cavey, T.J. Davidson, N.W. Decks, E.C Emrns, RR Harding, 1. Thomson, V.I'. Watson Members' Council A.J. Allnutt, P.J.E. Daly, P. Dwyer-Hickey, R Fuller, B. Jackson, J. Kessler, C. Monnickendam, L. Music, J.B. Nelson, K. Penton, P.G. Read, 1. Roberts, R Shepherd, R Velden, CH. Winter Branch Chairmen Midlands: J.W. Porter North West: 1. Knight Examiners A.J. Allnutt, MSc., Ph.D., rCA L. Bartlett, BSc., M.Phil., FCA, DCA E.M. Bruton, FCA, DCA CR Cavey, FCA S. Coelho, BSc., rCA, DCA AT Collins, BSc., Ph.D. B. Jackson, FCA, E.A. [obbins, BSc., CEng., fIMM, FCA C.B. Jones, BSc., Ph.D., FCA D.C. Kent, FCA R.D. Ross, BSc., FCA P. Sadler, SSc., PGS, PCA, DCA E. Stern, rCA, DCA Prof. 1. Sunagawa, DSc. M. Tilley, GC, FCA C Woodward. BSc., FCA, DCA The Gemmological Association and Gem Testing Laboratory of Great Britain 27 Greville Street, London ECIN 8SU Telephone: 071-404 3334 Fax: 071-404 8843 TheJournal of G(*mmn\i\erv X^T VOLUME 24 NUMBER 6 APRIL 1995 Editor Dr R.R. Harding Production Editor M.A. Burland Assistant Editors M.J. O'Donoghue P.G. Read Associate Editors S.M. Anderson London Dr C.E.S. Arps Leiden G. Bosshart Lucerne Dr A.T. Collins London Dr J.W.Harris Glasgow Prof. R.A. Howie Derbyshire DrJ.M.Ogden Cambridge Dr J.E. Shigley Santa Monica Prof. D.C. Smith Paris E. Stern London Prof. I. Sunagawa Tokyo Dr M. Superchi Milan CM. Woodward London Any opinions expressed in The Journal of Gemmology are understood to be the views of the contributors and not necessarily of the publishers. Cover Picture Watch set in a crystal of Colombian emerald found during excavations in Cheapside in the City of London in 1912. The crystal measures 42mm deep and 20mm across (see The Cheapside Hoard confusion', page 395) Photo: courtesy of the Museum of London. ISSN: 1355-4565 394 J. Gemm., 1995, 24, 6 In this issue... The topics covered in this issue of The Journal accessory on the well-established gem refrac- of Gemmology again comprise a range from the tometer and should lead to improved speed and historical to the modern. The first paper con accuracy of refractive index readings. The cerns a rather enigmatic hoard of jewellery and second paper describes the infrared microscope jewellers' materials discovered in London in and its application to certain problems difficult 1912. Mystery still surrounds the precise origin to solve by standard gemmological techniques. and recovery of the cheapside Hoard, but most With the rapid growth of information it of it is now on display in the Museum of becomes increasingly difficult to find the time to London. The Hoard has been attributed to the absorb the information of most relevance. But to early seventeenth century and is a fascinating absorb relevant information one must first find assemblage of precious stones and decorative it or be made aware of it. After that come the materials in a wide range of different qualities. processes of assimilation and assessment as to The gemmological identities of some excep its reliability. The compilation of abstracts of tional items augment the historical account of current investigations can speed this process the discovery of the Hoard and perhaps, with enormously and in this issue more than a the continued development of historical analy hundred abstracts relating both to important sis techniques, answers may yet be forthcoming aspects of gemmology and to related topics are for the still unsolved aspects of the Hoard's printed. origin. Diamonds continue to fascinate investigators Another source of continued speculation con of the depths of the earth and there are abstracts cerning its origin is the gem material moldavite. of significant papers on the variety of ages of It is now more or less agreed that the spread of diamond and of their chemical and isotopic specimens over areas formerly known as variation. At first sight these investigations may Bohemia and Moravia is the result of a massive seem of marginal interest to gemmologists but meteorite impact with the Earth in an area to the with the increasing possibilities of encountering east of Stuttgart in Germany. The energy treatments, synthetics and imitations on the released on impact melted the local materials market, fundamental information of this kind and in the glasses generated some very beauti could give rise to effective methods for identify ful inclusions which were preserved by the ing natural untreated stones. quenching process. These unusual phenomena Journals not normally seen by gemmologists are illustrated in the paper by Anthony de from time to time contain papers of consider Goutiere. able gemmological interest and potential and Glass of a different nature turned up in the one abstract printed here offers hope of being form of a cat's-eye cabochon among the items able to determine the origins of different submitted for testing at the Bahrain Laboratory. ambers. The World of Stones is a new journal Different synthetic corundums are also from Russia abstracted by Michael O'Donoghue described and, considering that much of the and this is beginning to reflect the increased Laboratory's work concerns natural and cul activity in gemmology in the area of the former tured pearls, the rather rare incidence of X-ray USSR. Some of the secrets of polishing are also radiographs which depict perfect pearl struc starting to come to light with detailed analysis ture is discussed. of surfaces and it seems that to obtain the best Two papers on instruments highlight the con results for certain stones it is crucial to find the tinuing quest towards more reliable gem best recipes. R.R.H. identification. One concerns development of an © Gemmological Association and Gem Testing Laboratory of Great Britain ISSN: 1355-4565 J. Gemm., 1995, 24, 6 The Cheapside Hoard confusion James G. Gosling Pattingham, Staffordshire WV6 7BU watches (see Figures 1-4), one of which is Abstract set in an emerald crystal (see also cover A summary of the accounts of when illustration). The collection gives a wonder and how the Cheapside Hoard, a collection ful insight into the social background of the of jewellery found in London in period and also raises many questions. 1912, is given. The role of G.F. Lawrence is described but some details Previous accounts are shrouded in mystery. Most of the There appears to be no eye-witness Hoard is displayed in the Museum of account of the actual discovery, no record London and gemmological details of of the date nor details of the find itself. The 1 some exceptional items are described. 1928 catalogue prepared by the then new director of the London Museum, Dr Mortimer Wheeler (later Sir Mortimer Wheeler, the charismatic participant of the Introduction 1950s television programme Animal, In the summer of 1912 a unique treasure Vegetable, Mineral) has been out of print of some 340 items was unearthed in for decades and is now virtually unobtain Cheapside near St. Paul's Cathedral in able. However, in that catalogue reference London. The Hoard is believed to be the is made to workmen digging on the site of 'stock in trade' of a Jacobean goldsmith, Wakefield House at the corner of Friday pawnbroker or perhaps a fence who buried Street and Cheapside, the property of the it, in unknown circumstances, in about Lord Mayor of London, in 1912. A 1630 and presumably was unable to return workman put his pick through a box which to claim it. lay, it is said, below a chalk floor. Although Most of the collection, known as the the box was much decayed, it was thought Cheapside Hoard, is now on display at the to have been fitted with trays, but further Museum of London in the Barbican, but in details of the recovery of the treasure are 1916 the treasure was divided largely lacking. between the London Museum and the In her book History of jewellery2 published Guildhall Museum - with some items in 1953, Joan Evans refers to 'The hoard going to the British Museum and some to from a jeweller's shop of about 1615 found the Victoria and Albert Museum. In 1976 beneath the floor of a cellar between St. the Museum of London was formed by the Paul's Cathedral and the London Central amalgamation of the London Museum and Post Office in 1912.' the Guildhall Museum which presented Another publication that refers to the the opportunity of bringing together most Cheapside Hoard is the Handbook of the of the Cheapside Hoard. The Hoard con Museum of London3 published in 1985. This tains elaborate gold and enamel chains, a refers to workmen demolishing an old rock crystal chalice, polished gems and © Gemmological Association and Gem Testing Laboratory of Great Britain ISSN: 1355-4565 396 J. Gemm., 1995, 24, 6 lished in 1991. He gives a date for the find The watch (A14162) shown on the of about 18 June 1912 when workmen were front cover has been dated to c. 1610. excavating a building site at the corner of The mechanism is badly corroded and Friday Street and Cheapside. They discov cannot be removed without the risk of ered 'a bucket' - rather than a box - damage.