I recently got hold of some old stoneware pottery glazes that had been tucked away for many many years. Rather than see them tossed away, I jumped at the chance to have them.
Two of them were labelled, one was a deep dark blue and the other a llight matt pale blue. (assuming the lids match whats in the buckets) The other two are a bit of a lucky dip as the names on the sides of the bucket had faded.
This one had a layer of moldy speckled like stuff floating on the top, so not sure if it was one of the glaze ingredients or if the top had come off and dirt etc had fallen in.
The only solution was to put it all though a fine sieve to filter out any stray solid bits and to help make it into a useable glaze consistancy. The seive was made out of some fine mesh pot rivotted onto the cut out lid of an old biscuit tin.....it doesnt look pretty but it does an amazing job.
This is what it looked like after putting it through the sieve 4 times. Nice and smooth and creamy. It was way to thick and was thinned down with water to a thin gravy consistancy.
This one was much the same. These old glazes had been sitting a long time and had all settled into the bottom in a nice hard layer. They take a bit of scraping and lots of stirring and elbow grease to break up all the lumps. A drill and paint mixer would have been handy!
This bucket was the worst, a very hard layer on the bottom. Water was added and I will leave it for a couple of days to soften up, then give it a good stir.
After about 3 hours of scraping, stirring and seiving I managed to get some test pieces dipped in them ready to pop in the next glaze firing. The test pieces have a pattern on the back to see how the glaze reacts over uneven surfaces etc. Each one had a matching letter code written on it so I know which colour came from which bucket.
There's a load in the kiln at the moment......cant wait until Sunday night to open it and see what colours we have.