There are many big Deltas printing in clay. It looks like a natural fit to create ceramic and pottery with Delta type machines since they are round and tall. Here is a new project by Olivier Van Herpt. Main feature of this custom design is that Oliviers DIY extuder uses hard clay and not clay-water mixture. This approach enables bigger objects with higher details and sizes up to 80 cm x 42 cm.
Source and more info: http://oliviervanherpt.com/functional-3d-printed-ceramics/