China's Ming dynasty lasted from 1368 to 1644. In terms of porcelain manufacture, this period is associated with a high level of technical and artistic refinement, with production centred around the imperial ceramic factory in Jiangxi province. Wares ranged from small wine bowls and so-called stem cups -- small bowls resting on a tall, tapering foot -- to ewers and various sizes and shapes of lidded jars. Identifying genuine Ming isn't easy, but the clues to doing so lie in the porcelain itself and the kinds of decoration used.
Look first at the porcelain itself. Because Chinese potters of this period were technically expert and well-supplied with raw materials, such as china clay, the porcelain should be flawlessly white. This is especially so with porcelain from the imperial factory, which exercised ruthless quality control, destroying inferior pieces.
Examine the kind of decoration. Many pieces from this period have surfaces adorned with incised and moulded patterns. Colour was used in a variety of subtle ways. In "au hau" or hidden decoration, these incised patterns were highlighted with a white slip (a thin solution of clay and water) that could only be seen in certain lights. On "doucai" wares, a design was sketched in blue, then filled in with washes of green, red, purple and yellow. But the Ming period is best known for its blue and white offerings, which ranged from a deep blue (made possible by the import of high-quality cobalt from the Middle East) to greyish and purplish blue (as the Chinese used their own, less-pure sources of cobalt).
Consider the subject matter portrayed in the decoration. Painted freehand by expert calligraphers, early Ming blue and white pieces often had floral designs contained within panels. Later blue and white wares depicted figures and whole landscapes. Meanwhile, coloured Ming pieces depicted fruit, fish, plants and even chickens.