Cross reference my notes on magnesite.

It is all about manipulating the plasticity of materials. All plasters and cements may be manipulated, but modern materials are typical designed to set very quickly, to suit industrial processes - thats were the money is. Old materials were not this way. If you had to stay on a job until 8 o'clock at night to trowel polish a surface - well - thats just the was it was. If you came back the next morning - too late, too sad.

Are you a carver or a modeller - that is the question - do you like to build up or take away. I know everybody uses both techniques - but what is faster for you?