I was looking for a way to produce a prototype of my paperweight, mainly to find out how heavy it would be. Without making a prototype I would never be able to calculate the volume as I am not a maths genius ......Thanks to Colin for suggesting the technique and Rory for making it happen. I used my printed 3D models to make the sand mould. what came out was so beautiful that all I wanted to do was to lock it in a cabinet only for display.