Hi

My friend has asked me to do this wedding cake for her next year. It looks simple enough untill i get to the middle parts which are black, any idea how this is done and what is used?

Thanks

It looks to me like the black are spacers (not cake). I could be wrong though. A blank canvas can make me tear my hair out. I can be wrong though. Hope this helps.

I agree, not cake.

could they be Styrofoam squares and covered with ribbon or material?

On WEtv the show Amazing Wedding cakes has an episode (306) where Cake Alchemy makes a jewel spacer similar to this using isomalt. This epiosde will be airing several times thru the month of November. You might go to WEtv.com and see when it airing and watch it.