Greek Marbles: Determination of Provenance by Isotopic Analysis Author(S): Harmon Craig and Valerie Craig Source: Science, New Series, Vol
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Greek Marbles: Determination of Provenance by Isotopic Analysis Author(s): Harmon Craig and Valerie Craig Source: Science, New Series, Vol. 176, No. 4033 (Apr. 28, 1972), pp. 401-403 Published by: American Association for the Advancement of Science Stable URL: http://www.jstor.org/stable/1734394 . Accessed: 08/04/2014 11:45 Your use of the JSTOR archive indicates your acceptance of the Terms & Conditions of Use, available at . http://www.jstor.org/page/info/about/policies/terms.jsp . JSTOR is a not-for-profit service that helps scholars, researchers, and students discover, use, and build upon a wide range of content in a trusted digital archive. We use information technology and tools to increase productivity and facilitate new forms of scholarship. For more information about JSTOR, please contact [email protected]. American Association for the Advancement of Science is collaborating with JSTOR to digitize, preserve and extend access to Science. http://www.jstor.org This content downloaded from 147.52.249.113 on Tue, 8 Apr 2014 11:45:54 AM All use subject to JSTOR Terms and Conditions the other hand, petrofabric studies are difficult and time consuming, require relatively large amounts of material, and depend on statistical treatments of what are, in these marbles, ratherpoor- ly developed fabrics. Our approach to this problem was Reports the idea that the 13C/12C and 18O/16O variations in Greek marbles probably provided the best chance for unique characterization by locality. The iso- topes 13C and 180 vary by at least 10 and 20 per mil (1 to 2 percent), re- Greek Marbles:Determination of spectively, in marbles from different areas (9), so that with two isotopes Provenanceby Isotopic Analysis there is a reasonable probabilityof ob- taining some distinctive differences. Abstract. A study has been made of carbon-13 and oxygen-18 variations in Moreover, we expected that the very Greek marbles from the ancient quarry localities of Naxos, Paros, Mount Hymet- process which originally formed the tus, and Mount Pentelikon. Parian, Hymettian, and Pentelic marbles can be clearly marblesmight well smooth out the vari- distinguished by the isotopic relationships; Naxian marbles fall into two groups ations within a single quarryingarea by characterized by different oxygen-18/oxygen-16 ratios. Ten archeological sam- local isotopic equilibration with fluid ples were also analyzed; the isotopic data indicate that the "Theseion" is made of phases. In general both these expecta- Pentelic marble and a block in the Treasury of Siphnos at Delphi is probably tions were fulfilled. Parian marble. We made detailed collections in the four major quarrying areas which pro- The problem of identifying the local- sen (7) were able to characterizeMar- vided marble for statuary and building ity from which a given specimen of mara and Parian marble as low in Mn, purposes in ancient Greece (10). In Greek marble was quarried has been none of these methods has been gen- each area we concentrated our sam- studied for almost 100 years (1). In erally very successful (8). Trace ele- pling at the sites of ancient quarries, as addition to the obvious applications ment studies suffer inherently from the indicated by old chisel marks, worked such as detection of copies and for- high variability in concentration (fac- faces, grooves, and other evidence. geries (2, p. 189) there are more gen- tors of over 100 for Na and Mn) Samples were collected over the maxi- eral problems of great importance due to highly localized interactionwith mum extent of each locality and from which could be solved by a method inclusions and surrounding rocks. On representativephases, in order to de- capable of uniquely assigning a piece of marble to its of The place origin. 7 major quarryinglocalities in use from preclassical to Hellenistic and Roman periods shifted successively from the Cycladic islands of Naxos, and later Paros, to Mount Pentelikon on the At- tic mainland, and finally during Roman times, to nearby Mount Hymettus (1; 2, p. 137; 3). Thus in many instances the specification of the provenance of a piece of statuary or a building can be used to date the object from the known periods of quarryingoperations in each area (4). Finally, there are geological problems at hand such as the question of whether the Pentelic and Hymettian marbles represent two formations or a single formation repeated by folding or faulting (5). Methods applied to Greek marbles for provenance determination in the past include petrographic techniques (1, 3), petrofabric studies (3, 6), and Na and Mn analysis by neutron acti- -9 -8 -7 -6 -5 -4 -3 -2 -1 vation (7). Although Herz and Pritch- 8018 (%o) ett (5) were able to solve a problem of Fig. 1. Carbon-13and oxygen-18variations in marble samples from ancient Greek a mismatch of inscription fragments by quarriesrelative to the PDB isotopic standard.Triangles denote some of the ar- a foliation study, and Ryback and Nis- cheologicalsamples listed in Table 1. 28 APRIL 1972 401 This content downloaded from 147.52.249.113 on Tue, 8 Apr 2014 11:45:54 AM All use subject to JSTOR Terms and Conditions Table 1. Isotopic analyses of archeological marble samples. where R is the ratio 13C/12C or 18O/ 160 and R+ is the ratio in the PDB Sam- /ac80 Probable ple Description (per mil) (per mil) prove- standard. The mass spectrometric No. nance methods and calculations have been de- A-1 Athens: "Theseion" (Hephaesteion) 2.63 -7.90 Pentelic scribed (14). The analytical precision is in the Agora, column on north + 0.05 per mil. side On the 13C-180 diagram, the marbles A-2 Athens: basal slab on south side of 2.63 -8.03 Pentelic fall into well-defined groups with the "Theseion" possible exception of certain Naxian D-1 Delphi: carved block lying inside 3.89 -3.10 Parian and Pentelic varieties. The Parian mar- Treasury of Siphnos bles are unique in having the highest D-2 Delphi: drum of column of the 1.96 -4.15 ? 813C values of the Greek specimens Naxian Sphinx and all of the marbles studied by Baer- E-1 Epidaurus: carved block (lintel?), 2.01 -1.12 ? 10 m from Tholos tschi (9). These marbles resemble algal carbonates and travertines in their high E-2 Epidaurus: Corinthian capital next 2.16 -0.78 ? to the "triple circle" of Tholos 13C values, and this resemblance to- gether with the high purity leads us to E-3 Epidaurus: cut slab of white marble, 2.58 -3.96 ? 13 m from Tholos suspect that they originated as a chemi- cal N-43 Naxos: Apollon Gate, Palatia, 1.67 -5.51 Naxian precipitate (15). Naxos Harbour; flake from inside Pentelic and Naxian marbles are of gate much lower in 180 than Parian and N-46 Naxos: Apollon Gate, large block at 1.64 -5.35 Naxian Hymettian marbles, a feature which is foot of hill toward Naxos generally due to interaction with me- C-1 Caesarea, Israel: Corinthian capital 3.51 -2.64 ? teoric waters at elevated temperatures of grey marble (9). The Pentelic marbles are also higher in 13C than almost all of the marbles studied by Baertschi, and the termine the variability in each area. A Hymettian marble, Mount Hymettus, Naxian and Hymettian marbles fall in total of 170 quarry samples and some southeast of Athens, on the western the upper part of his range. Only the 20 archeological samples were taken. slope (13). The marbles are grey, white, Hymettian marbles fall within the gen- The marbles studied, in order of age and blue, and are the "upper marble" of eral 13C-180 trend outlined by the mar- of the workings, were as follows. Lepsius (1). Seven ancient quarries ble samples in Baertschi's work. It is Naxian marble, on the island of were located and sampled. noteworthy that the isotopic data clearly Naxos in the Cyclades (6th and 7th General descriptions of these mar- confirm Lepsius's conclusion (1) that centuries). The ancient Naxian quarries bles are given in the references (1, 3, Hymettian and Pentelic marbles ("up- occur in two main localities, in two 5). The marbles are often (though not per and lower" marbles) are different formations (11). Near Kinidaros, in the always) distinguishable with high prob- geological formations. central interior, ancient quarries (prob- ability in outcrop or fresh hand speci- The Naxian marbles so far studied ably used only locally) occur in the men (Naxian marble is generally coarse fall into two groups with respect to Keramoti marble. On the north point grained, Hymettian marble is often grey 818O values. Each of these isotopic sub- of the island, at Apollon, the ancient to blue and banded), but cannot be dis- groups contains samples from both the quarries are in the Amomaxi marble, tinguished with certainty from each Naxian localities studied. Lepsius (1) which is separated from the older Kera- other, or from other marbles, in build- noted that there were two types of moti marble by Komiaki schist. Each ings and statuary. Both Pentelic and marble in the vicinity of the Apollon of these ancient sites is marked by the Hymettian marbles occur on each of Kouros, one of which closely resem- presence of a very large recumbent these mountains (1). bles the roof tiles of the "Old Temple" figure (Kouros), the earliest Greek stat- In this initial study a statistical sam- of the Acropolis and the Temple of uary. pling of about 35 percent of the sam- Zeus in Olympia. The isotopic data Parian marble, on the Cycladic island ples was selected for analysis. Further indicate that both these marbles prob- of Paros (5th and 6th centuries).