Hi everyone tonight:

You are right Timbeal, What you were working with was not the real slacked burnt lime, it also is a powder but very volatile, and once slacked will remain in a putty form for a very long time, provided that it is kept wet, some dug a hole in the ground and stored it there, we did that at Ucv and retrieved some as we needed it for demonstration purposes and maintenance on the historic structures.

This same putty mixture by the way is what is used for the final third layer, as you build up the (3) coats on a wall surface, it is put on very sparingly and trowelled to a very smooth surface, and when dry is very hard, and when tapped lightly will ring