On Lustre
There are several different ways of making `Lustre`. The pieces in this exhibition all involve the process of Reduced In-glaze Lustre – a complex specialized technique to form on the surface of a glaze a film of metal (usually gold, silver or copper) or an iridescent sheen.
If the glaze is saturated with a salt or fine particles of the metal then an opaque surface results and dilutions of the metals produce iridescence or isolations of individual colours from the multi-coloured iridescence. I find silver the most versatile and as well as making solid silver surfaces it can make a range of delightful blues, turquoise, greens, yellows and orange and very rarely an amazing jewel-like emerald. Copper is the most reliable and in addition to the familiar bright copper a range of reds and purples. Gold used on its own is the most problematic. It volatilizes rather easily and disappears into the ether. Its greatest value is to brighten and extend the range of the other two metals. However, the heavenly purple it very occasionally produces makes it irresistible to attempt. Thus with copper, silver and gold, the spectrum can be covered. Sadly it is not possible to produce precise lustre colours at will.
Lustre glazed ceramics were first produced in AD 9th Century in Iraq and historians speculate that the technique was developed to produce inexpensive versions of solid gold or silver objects. This is questionable given the complexity, expense and unreliability of the firing process. Archaeological excavations of ancient kiln sites have revealed spoil heaps of gigantic proportions, indicating huge failure rates, which would indicate that potters were pursuing objects with their own aesthetic integrity – hence the exquisite early Persian lustred ceramics where lustre is used to enhance devotional texts on bowls and to decorate extravagant and expensive `Palace` wares.
The much-quoted text from the famous potter Picolpasso that `oft-times of 100 pieces of work put to the fire scarce six are good` holds almost as true today as it did half a millennium ago. Despite enormous advances in kiln technology, digital temperature control and glaze analysis the process continues to defy reliable commercial production, companies and individual potters generally abandon the process discouraged by the seemingly capricious and uncontrollable nature of the technique and its accompanying failures.
This said I am amazed to find that I have been working exclusively in Lustre for 50 years. Fortunately, I have learnt a trick or two and my failure rate has become rather less alarming. However, one must conclude that it will never be possible to fully master the technique. There are too many variables. The window of opportunity when lustres form is tiny. The temperature in the kiln must be held at precisely the right temperature for the particular glaze being used, in exactly the correct degree of reduction (absence of oxygen). The weather has to be taken into consideration as well. I find high humidity favours lustre development and high winds can be a problem in a combustion kiln.
One could go on endlessly about the problems involved in firing lustres. There seems to be no end to them. However, for me, the rewards greatly outweigh the frustrations. When the process works the colours and textures are thrilling and I feel the resulting pots are like no others. I must enjoy the challenge and wish I had another 50 years to perfect the process. Maybe one day I will.
Sutton Taylor, 2021