Delft casting - beginner help!

[Victoria]

Hi all,

I'm just about to have a go at delft casting & was wondering how thin a piece of metal can be cast? I make lots of cufflinks like those in the attached photo - the base is made out of 1.85mm sheet & the design is cut out of 0.5mm sheet. Could I cast these? Should I cast the design separately & solder it on or cast as one piece? I could change the proportions a bit so the base is 1.5mm & the design is 0.9mm, say, so there's more definition?

Thanks!
Victoria