glass and glaze

Below are two images of a recent sculpture by Paola Kassakowska. One was taken before it was fired and the other is a detail of the glazed surface of the face. In case some of our viewers are not familiar with the word "glaze", here is the basic description of what glaze is made of (from wikipedia)

Ceramic glaze raw materials generally include silica, which will be the main glass former. Various metal oxides, such as sodium, potassiumand calcium, act as a flux to lower the melting temperature. Alumina, often derived from clay, stiffens the molten glaze to prevent it from running off the piece. Colorants, such as iron oxide, copper carbonate or cobalt carbonate, and sometimes opacifiers such as tin oxide orzirconium oxide, are used to modify the visual appearance of the fired glaze.

 

It is still not obvious, how glaze works, unless one is familiar with glass. I leave you a beautiful film where you can see how glass behaves in the making. A contrast between the traditional glass making and the industrial machines that produce glass items en masse.

Glas Glas won master film maker Bert Haanstra a well-deserved Academy Award® for Best Short Documentary in 1959. The film contrasts the production of hand made crystal from the Royal Leerdam Glass Factory with automated bottle making machines in the Netherlands. An industrial film with a bebop heart, its lyrical use of light and sound still looks and sounds fabulous, nearly 60 years after it was made. Director Biography: Bert Haanstra (May 1916 – October 1997), was an internationally acclaimed Dutch film maker with a career spanning four decades. Though he made several forays into fictional cinema, it is his documentaries, which cast a sidelong and often idiosyncratic glance at the human animal, for which he is best known. Director: Bert Haanstra Producer: Government of the Netherlands Running Time: 10 minutes Website: www.berthaanstra.nl/english.html