I actually just saw his actual ring
. It's gold with a single, small diamond inlaid in the band.
As for your Kikoken, I would recommend taking 2 balls, 1 large Orange/yellow, 1small blue/white. Then hot glue them together.
Then just cover parts of them in blue and white silk essence to create the "flames" I suppose craft wire could be used to create a "skeleton" to which the silk essence can be attached.
If that doesn't work, I'm sure I can help you figure something else out that may work