super piece, easily identified. One of my top contenders for collectibles of the future.
Liuligongfang is very easy to identify as it us usually always marked. The distinctive four character seal mark on this piece reads 'Liuligongfang'. That said, there are several firms on the Chinese mainland who are also capable of making wares of this quality (and if Liuligongfang becomes more widely recognised I wouldn't be surprised to see fakes appearing on the market).
I spent some time with a firm named Jin Bo who were making similar Pate-de-Cristal wares back in 2007 (this eagle sculpture was made by them http://glassgallery.yobunny.org.uk/displayimage.php?pos=-10518
). They use essentially the same methods as Liuligongfang. A clay master is sculpted from which an elastomer mould is taken. This elastomer mould is then used to cast as many wax positives as are required. These are then further finished by hand to add in the fine details, then encased in plaster of paris and the wax melted out. Thus numerous examples can be made from one model, though it's a fairly labour intensive process. The moulds are filled with crushed glass and fired in large electric kilns. The annealing happens in the kilns as they cool over a period of several days. After release, the pieces still need extensive finishing to remove the protrusions formed from the channels in the mould, etc. The failure rate was also fairly high with some pieces breaking when the plaster was removed. The need for highly skilled labour and the high failure rate explains why these pieces are expensive even in China where manufacturing costs are typically low.
I hope to research more makers and collect more catalogues when I go back to China at the end of the year.
The technique used is a little different from that used at Caithness and other smaller studios where a binder such as PVA is mixed with fine powders to produce a smooth paste. In the Chinese and Taiwanese firms, no binder is used and the mould can be filled with pieces ranging from fine powders to large chunks depending on the desired effect. The glass was delivered to Jin Bo in the form of coloured discs which were then broken up on the premises depending on what was required. The lack of a binder though means that it's hard to control the distribution of colour. While careful filling of the mould helps, there will always be some flow when the piece is fired. The end result though tends to be brighter and more translucent than traditional (powders with binder) pate-de-verre.
It is the fine quality of the models and moulds which give much of the character to the pieces. Jin Bo had a very skilled sculptor to create the models and finish the wax intermediates. Equally, to create the finished works also needs an understanding of how the glass will act in the mould, where to put the fill-holes, will the piece survive extraction?, etc. This understanding takes time to acquire and is I think, one reason why a lot of pate-de-verre sticks to simpler, more primitive styles.