Chinese silk

China-saure, /. quinic acid, -seide, /. China silk Chinese silk, -silber, n. China silver (a plated alloy). 

Fabric. The silk fabric used in this work was an unweighted plain woven Chinese silk habutae (Testfabrics, Inc., Middlesex, NJ, style 605) having 126 ends/in. (37.6 denier), 117 picks/in. (32.6 denier) and weighing 1.11 oz./yd. The fabric as received had been degummed [1]. All fabric samples were taken from the same bolt. 

Problems of classification of 18th century painted-printed Chinese and Western silk textiles are discussed with emphasis on how nondestructive X-ray fluorescent (XRF) analyses of pigment-dye pastes and paints can be combined with visually observable physical characteristics, painterly techniques, and art historical research to separate Chinese silks from Western ones. This unique documentation process is the result of our joint, 2-year study and shows how textile connoisseurship can be reinforced with scientific data. Thirty painted-printed 18th century silks from the textile and costume collections of the Cooper-Hewitt Museum The Metropolitan Museum of Art in New York Musee Historique des Tissus in Lyon, France National Museum of American History Philadelphia Museum of Art Rhode Island Historical Society and The Henry Francis du Pont Winterthur Museum were examined and analyzed by XRF for this study. 

In England, the British East India Company had a monopoly on trade with the East. An established sailing pattern for the British East India Company ships was to leave, in midwinter, from London for Canton, China, and return 13-14 months later. Meticulous records of this company s trade, as a result of silk being an important commodity imported directly from China, are housed at the India Office Library and Records in London. These records provide valuable information and documentation for several of the Chinese silk characteristics. 

The four physical characteristics of silks of Chinese origin (Table I) are the result of Lee-Whitmans research on plain and patterned silks (I) and our observations of the Chinese silks available to us for study. 

In Chinese silks of both plain weave and satin weave, the selvedges were observed to contrast in color, and at times in weave, from the ground color of the fabric. (White Chinese silks often had yellow or green selvedges.) Such a contrast was not regularly found on Western silks. 

Fabric finish soft sheen and feel sometimes soft sheen and feel, but not to the same extent as Chinese silks... 

The fourth physical characteristic of Chinese silks, a soft "hand , we feel is the result of calendering, which is a characteristic mechanical method for finishing silks in China (Figure 3). This process involves a stone base plate, a wooden roller, and a heavy rocking stone. The silk fabric is placed on a roller and subjected to intense pressure as a workman rocks back and forth on a rocking stone. This process leaves an unmistakable sheen and soft clinging hand that can distinguish Chinese silks from Western ones. 

Figure 5. Seepage of the black-ink outline to the back of an 18th century Chinese silk. (Acc. No. 18032, courtesy of the Musee Historique des...

Consistency of Coloring Matter. With the exception of the underlying ink outline, all surface coloration on Chinese silks appears to be due to the use of thick and opaque paints or pigment and dye pastes. 

The coloration remains on the surface of the fabric. The pigment and dye pastes used to print Western silks were much less viscous than the paints and pastes used on Chinese silks. 

This painting technique is related to a centuries-old Chinese tradition for naturalistic flower painting in which white paint is used to form a base to give greater depth to the paint laid over it. Also, details can be painted onto the white paint without a loss of clarity, and it can be mixed with other colors to alter the strength of the tones (6). All 22 Chinese silks available for study showed this particular characteristic. 

Figure 10. An 18th century painted Chinese silk showing heavy use of white lead ground layer and copper green pigment. (Acc. No. 32554, courtesy of the Mus ee Historique des Tissus, Lyon.)...

Positive wet microchemical and microscopic identifications were permitted for the copper greens on only two of the Chinese silks. In both cases the result was the copper carbonate pigment malachite, which confirmed that Chinese copper greens were malachite and the Western ones were verdigris. A positive identification should be performed whenever conservation conditions permit it and trained personnel are available (7). 

BROWN Pigments. A distinction is also apparent between the brown pigments used on the Chinese and Western painted and printed silks that were available to us for study. XRF analyses revealed that the various shades of brown present on the Chinese silks were iron oxide pigments, whereas the brown colors present on the Western silks were organic pigments (see Table V and Figure 11 for Western browns and Table VI and Figure 12 for Chinese browns). 

Figure 15. W oven silver outline visible in flower petals and leaves on an 18th century Chinese silk fragment. (Acc. No. 42.115.29, courtesy of The Metropolitan Museum of Art. Gift of Nellie B. Hussey, 1942.)...

The botanical quality of ginseng preparations is problematic (1). For instance, when a case of neonatal andro-genization was associated with maternal use of Siberian ginseng tablets during pregnancy, botanical analysis showed that the incriminated material almost certainly came from Periploca sepium (Chinese silk vine) (2). 

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