19 glass, and as being carved, leading to their acceptance among some experts as evidence of early cameo overlay. While I accept the likelihood of early cameo overlays, I do not think these cups were of that type of carving. A great deal of uncarved Chinese glass is made up of different colored layers known as uncarved overlay ( sutao ). These could then be left plain, engraved just on the upper surface, or carved through to create cameos. Cheng ’ s cups were decorated, I believe, with an engraved surface design, a common enough type of early eighteenth-century cup. But regardless of that, these cups prove the existence of overlay, whether carved or not, by 1708, and once the relatively simple art of laying one color of glass over another was mastered, carving them through to reveal the lower level and create a cameo overlay would have been so obvious to the Chinese lapidary that it would probably have happened almost immediately. Figure 10 might be a carved monochrome from the late Kangxi period. Wang Shizhen does not tell us what color green was made at the Imperial glassworks, but there were probably various different greens produced, of which this may be one. Again, it seems to have been buried, to judge from the degraded surface, which might give it the impression of greater age than it has, but it could be from the Kangxi reign. A still stronger candidate is the magnificent realgar glass bottle from the Bloch Collection which is a cameo overlay, although a subtle one ( fig. 11 ). This is exactly what one might expect of a very early overlay, where a random-colored surface is used like a jade pebble covered in dark skin. The chi dragon decoration on both this and the last would also suggest a courtly origin, since this was one of the most popular of all designs on Imperial snuff bottles from the Qing dynasty. Realgar glass was unquestionably one of the earlier colors of glass produced. There are various pieces of realgar glass in the Sloan Bequest to the British Museum, given in 1753, although collected earlier, 11 and there is a set of ten realgar glass cups in Denmark, which were purchased in Guangzhou and brought back to Europe on the “ Kronprins Christian ” in 1732. 12 It was also certainly produced at the Imperial Workshops. There remains in the Imperial Collection in Beijing realgar glass bearing the Yongzheng reign mark. 13 Also in favor of this bottle being very early are the crystalline degradation of the green coloring of the surface and the style of the chi dragons, which are as powerful and individual as any known on a snuff bottle and typical of the early eighteenth century. Choosing very early candidates for the more common range of brightly contrasting cameo overlays is more difficult, and it may be that these were not developed until the last years of the reign and that surviving examples are extremely rare. There is nothing known which could be attributed to the Kangxi over, say, the Yongzheng period with any certainty, but there are some possibilities. Figure 12 , with its small size, elegantly realistic carving, and known early colors could be from the late Kangxi period. It is one of a small group more likely to date from a little later, perhaps, but they may have first been produced prior to 1722. There is also a group of deeply carved, dark ruby-red overlay bottles represented by figure 13 , which are Fig. 12. Ruby-red overlay on translucent white glass carved with a continuous design on each side of two bats and three peaches on branches, 1710–1760. Bloch Collection. Fig. 13. Deep ruby-red overlay on milky glass ground carved with archaistic fenghuang and four chi dragons, 1720–1780. Bloch Collection.