Authenticity and connoisseurship
Evidence and circumstances
While the materials of Chinese painting have been remarkably stable over a long period, certain specific aspects of manufacture have varied and can reasonably point to the age of a painting. Detailed study of silk reveals different qualities of weaving and standard sizes at different times, while with paper there are types and qualities that prevailed from one epoch to the next. There have also been materials that were used for a time and then abandoned. An example of this is satin which was popular in the later Ming and early Qing but which has rarely been used since.
Ink tone, density and lustre point to sources and times of manufacture. And similar points can be raised in respect to pigments.
Material aspects of seals also can be studied historically. Where many seals from different periods are present, the cinnabar colouring should be varied (– not to do so represents incompetent faking!) In addition, some research can be done on the likely character of the seal colour and material for any given epoch – it is known, for instance, that most Ming seals were in a water-soluble and now more lighter toned red (while more recent centuries have seen the use of oil-based colourant.)
More scientific tests of age such as carbon dating are difficult owing to repeated remounting. A sample of a legitimately ancient piece may well yield a more recent age owing to the presence of later glue, re-touched ink and so forth.
It is often said that it is a good sign if an artwork has been loved and treasured by generations of owners. This results not only in an accumulation of inscriptions and seals, but may also include fine mounting and the addition of decorative paper and cloth, a tailored cloth bag, a jade fastener and fine finials for scroll, or a bespoke box. The addition of these elements often comes over many centuries, subsequent owners adding and adjusting. Often this complements a good remounting of the painting itself.
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| Dong Qichang 董其昌 (1555-1636) Handscroll (dated 1615) Ink on satin 53.3 x 910 cm. Detail. Private collection | Zitan box in shape of bamboo, with mother-of-pearl inlay Silk bag for painting of WEN Zhengming 文徵明 (1470-1559) |