Royalty arrangements for designs?

Hello again,

I’ve been asked to make some designs for a company marketing a new
simulated stone, and they are interested in producing the designs on
a royalty basis. I would provide the original, they would do all the
production/casting of the model/models we agree on and sell them w/
their stones in them to various types of resellers/chain stores. I
understand it would be marketed under my name/company/design name.
What kinds of arrangements are normal? Is the royalty based on a set
amount per piece? An initial price for design plus a royalty? Or a
percentage based royalty? Does anyone have any experience with this
type of deal?

Thanks,
Jeanne

Jeanne Rhodes Moen
Kristiansand, Norway
http://www.jeanniusdesigns.com