American Clay. He had used it in a previous clients home and was extremely pleased with the product so I thought I would pass on this gem of knowledge to you.
American Clay is different from other plasters. It was brought about by a chemist and interior designer partnership seeking an environmentally friendly plaster choice that also had an element of historical value. Clay was long used in history as an important building material. This patented product comes in a variety of colors and textures to create the look you desire be it a residential or commercial space, contemporary or traditional look. Find out more about this product here. They are very happy to help design professionals since one of the co-founders is a designer herself and understands the industry from both sides.
Take a look at a few photos from their portfolio:
Images from American Clay