Hi there, The clay is called Steadtler Fimo Air Light. It's an airdrying clay and dries extremely lightweight, so is ideal for using on the dolls, no balance problems when I use it on the heads! It's a spongey texture, but easy to smooth and delightful to work with when you get used to it. It's just not quite as dense as usual clays, but it's my favourite now!
It comes in 250g packets and I'm in the UK, so it costs me about £8 a packet. Hope this helps.
The epoxy clay is smoothed up the leg and roughened to look like hair/fur. The Milliput sets rock hard after several hours and takes paint pretty well. Hope this helps.
It does have a slight "spongey" (marshmallowy) texture to it when working with it, but it smooths beautifully and as it's so light in weight, it's great to use on the dolls, as no risk of overbalancing. I have used it extensively on my dolls, on their bodies, and heads particularly. It takes acrylic paint well when dry.
I did use a basic air dry clay within the base of the Weeping Angel customs, for stability, but for the hair, dress, wings and also the deer ears, I used the light air dry clay. The tooth fairy's ears and also Neytiri's ears and the sculpting on her face (nose) was the light clay. I hope this helps!