They are bronze cast with separate bottom, soldered in. This bottom is also handworked as "timber" and has seal in archaic (clerical?) characters on each vase. The surface is black and is decorated by some early form of enamel, not cloisonne but looking rather as a coloured clay, similar to "mastica" used in Europe before 18th century. The colours are hardly visible, but one can distinguish green and red, and maybe yellow. The surface of the colours is rather coarse, not "polished". There is no separating wires used, surface is engraved and indents filled with this coloured clay. To me it looks a very old technology.
There is also a gold wash ornaments drawn over the "enamel", some of this wash has been lost but mainly its OK. Inside the opening of the vases decoration continues for an inch or more.
If there is a buyer for it then it is better to do it through eBay/PayPal system unless the buyer has an agent in NZ.
