Chemistry and art work together - Journal of Chemical Education (ACS

Describes a chemical investigation to determine whether the surfaces of Chinese, Hui-hsien pottery was produced by a lacquering process...
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JOURNAL OF CHEMICAL EDUCATION

396

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CHEMISTRY AND ART WORK TOGETHER LEONORA NEUFFER BILGER, GUSTAV ECKE, and CLAUDE HORAN University of Hawaii, Honolulu, Hawaii

IT

IS well known that natural lacquer, a product of the lacquer tree (Plus uernicifera) of the Orient,' has had an important and significant place in the arts of China and Japan. Its use dates back 2500 or more years and its lasting qualities are phenomenal. I n recent years, the lacquer of the Orient became an important consideration, both in England and America, in connection with a controversy existing among specialists in the ceramic arts of China. I n the fifth pre-Christian century Chinese ceramicists produced a pottery characterized by very shiny, hard, black surfaces which came to be known as Hui-hsien ware. Following the Japanese occupation of North China, black statuettes and figurines, claimed t o be genuine Hui-hsien specimens and presumably brought to Peiping by runners from Hui-hsien, made their appearance in the art markets of Peiping and Shanghai and found their way into the collections and museums of Japan, China, Europe, and America. A widespread controversy highly significant to specialists in the Chinese ceramic arts arose with regard to the authenticity of these shiny, black-surfaced articles. Finally the difference of opinion came to be based upon whether the genuine Hui-hsien pottery received its unique shiny black surfacing by a burnishing or by a lacquering process. Folloll.ing a meticulous study of the character of Hui-hsien ware and an intensive experimental study of competing specimens, the declaration mas made by a modern ceramics specialiste that

' HARADA,JIRO,"A Glimpse of Japanese Ideals," Kokusai Bunka Shinkokai, Tokyo,Japan, 1937. ' HORAN,CLAUDE,Bulletin, Hmolulu A d m y of Arts, 13, No. 4 (1951).

AUGUST. 1953

397

were run on the pure solvents and residues were entirely absent. Before the solvent treatment, it mas impossible to transfer any black material to a cloth or to the hands even by vigorous and persistent abrasion. After the extensive extraction process, the surface of the bell v a s covered with a loose black powder resembling lamp black which was easily ruhhed off hy a cloth or by the fingers.

neither burnishing nor reduction alone, nor any of five familiar causes of the glossing of pottery surfaces, could have brought about the actual appearance of the authentic Nui-hsien objects. The utilization of various other criteria of a ceramics specialist3 failed to provide a basis for distinguishing with certainty the marks of authenticity from those of fraud. It therefore became apparent t,hat it was necessary t o determine whether or not the surfaces of genuine Hui-hsien pottery were produced by a lacquering process. The Honolulu Academy of Arts made available for laboratory investigation a precious 7'lrinch Cha'han-kuo (warring states) pottery bell, Figure 1, known to he a tme Hui-hien ~pecimen.~The outside surface of the bell is sharply crackled, a condition associated by ceramicists with the ancient use of lacquer, Figure 2. Permission was granted for experimentation on the inside of the bell. Preliminary t,estswith a variety of organic solvents on very small areas showed that t,he clean, hard, permaneut surface could be penetrated, softened, arid reduced to a dull claylike surface, gray in color. At the same time a black, carbonaceous po~vderx a s released. Solvents were then applied to larger surface areas with the same results. Figure 3 shows a treated area and also gives evidence, from the streaked appearance, of the use of a brush in lacquer application. Amy1 acetate in 17 separate, small portions, ethylene glycol monomethyl ether in 24 portions, and ethyleue glycol monoethyl ether in 11 portions were applied consecutively, filtered separately, each partially evaporated, and finally combined on a watch glass for complete evaporation. A very thin, transparent, almost colorless, hard film with the appearance and character of lacquer remained on the watch-glass receiver. The uhotoaraph of the film is shown in Figure 4. Blanks a E c ~ EGUSTAT, , Arlibus Asiae, 15, No. 4 (1953). 'Illustrations by courtesy of the Honolulu Academy of Arts, and A ~ t i b u sAsiae, Ascona.

The conclusion lvas drawn -that the black, glazed, hard, permanent surface on the Chan-kuo pottery bell had been produced by a lacquering process. The rewlts were in agreement ~viththe expert opinious and measured judgment of t ~ specialists, o the latter t,wo co-authors of this paper.