Well I made another casting from the mold, this time using a material I hadn't heard of before - Jesmonite. I think it's a mixture of plaster and resin so it's fairly strong when set. Not surprisingly it went a bit pear shaped as I left the mixture in the mold overnight (to set). Unfortunately when I tried to remove the cast it had set to the mold. Did I mention that you live and learn? I think that next time I should do a bit of research into the correct procedure before I go casting again.
So the mold had to be broken to get the Jesmonite cast out. As it happens there were bits of the plaster mold still stuck to the Jesmonite which actually looked cool so I decided to leave them there for now.

O.k. so maybe it looks a bit wierd but there's potential for experimenting. Any way if you think that looks wierd check out the next image. I decided to try and faintly colour the cracks that occured in the first wax cast. On hindsight I guess using watered down ink or even watercolour paint might have worked better, but at the time I used watered down acrylic paint which didn't really achieve the result I was going for. As you can see from the image the whole cast ended up coloured. Turned into a bit af a happy accident though as it gave the whole thing a new dimension. It's a bit freaky though - you need to see it in the flesh, so to speak. Still, it's given me a new angle for experimenting with ideas so i'll keep ye posted.