Richard Bideau learnt the basics of pottery from his mother, the well-known Lancashire potter Joan Bideau. Later he developed an interest in glazes which followed from his educational background in the natural sciences. Starting from a number of published recipes for crystalline glazes in 1996, he has, over the years, conducted many thousands of crystalline tests resulting in a range of glazes that are now uniquely his own. His work consists primarily of porcelain, thrown and finely turned in traditional forms such as bowls and bottles. Never content with his current glazes and forms, Richard is continually experimenting along new lines and finds the thrill of new discovery undiminished.

Crystalline Glazes

The crystalline glaze derives its spectacular appearance from the presence of zinc silicate (Willemite) crystals within the glaze matrix. In a 'conventional' glaze, crystals are often considered to be a flaw and steps are taken to ensure that they are either completely absent, or very small and not noticeable. Crystalline glazes are specially formulated to permit the growth of large crystals. The glaze recipe includes an unusually large proportion of zinc oxide, an unusually small amount of aluminium oxide together with a vigorous flux such as sodium or potassium oxide. A special kiln firing is required. Until the maximum temperature of between 1275°C (2327°F) and 1290°C (2354°F) the firing proceeds as it would for a conventional glaze. After this the temperature is allowed to fall rapidly to around 1050°C - 1120°C (1922°F - 2048°F). The temperature is held in this range for a number of hours to allow crystals to grow. The kiln is then allowed to cool normally. The oxides of cobalt, iron, nickel, manganese and copper provide colour in the glaze. The crystals absorb the colourant in different amounts to the background glaze matrix giving striking contrasts. The fascination in the glaze derives partially from its unpredictability; effects can be controlled to some extent but the same effect can never be reproduced exactly.