I've been thinking about trying a pot melt for ages, with so much scrap glass in the studio it was time to give it a go. The technique allows you to combine compatible glass (same COE) in a pot and heat it to a very high temperature. As the temperature of the glass rises and becomes liquid it runs out of openings in the bottom of your pot. The thick drip can result in a radial pattern that spirals outward onto a prepared kiln shelf or container.
I was convinced the kiln shelf would be ruined with molten glass everywhere so used a terracotta flower pot saucer to catch the liquid glass which I prepared with kiln wash and lined with a piece of thinfire paper (conflicting advice online for this but it worked for me). The flower pot was loaded with about 1.3 kg of scrap glass in clear and shades of blue and green.
This is the resulting disc of glass as it came out of the kiln, there was a raised spot in the centre where the glass flowed from the pot, which I ground off and then fired the disc again at full fuse.
And finally slumped over a spherical dish mould. I love the spiral pattern formed in the glass, will definitely be trying this again. My top tip is don't open the kiln too soon (like I did), the thermal shock cracked the flower pot, so next time I'll let the kiln cool down for a day after the firing schedule has finished.