What kind of clay do you use? I use FIMO and it's not this translucent at all. Or maybe I'm doing it wrong? It's frustrating. I see stuff done with liquid clay too, and they are almost transparent. I can't get mine to be that transparent.
Fimo is the least translucent of all of them and it gets little cracks in it sometimes. Try premo, that's what I use. Bake your translucent stuff with a cover over it so it doesn't discolor and cook at a low temp like 200 for about 20 - 30 min. I varnished this to make it shiny and i also use Black Pearl salon gloves to the piece a very smooth glass like finish with no need to sand or buff.
Fimeo is great because the color doesn't change at all when you bake it. Some of the other kinds of clay are very nice as well and work better for some things. I have found fimo to be a bit firmer then other clays. Never use sculpyIII it sucks. Primo is great!