I've tried using colour pencils on different colour papaers including black but found it difficult to get vivid colours. I drew the Morgana picture in my gallery originally on black paper but wasn't happy with the result. I need to give it a go again. Prismacolor pencils might work better as they are more waxy than the polychromos I use. I've got some brown canson paper which I'm getting better results with. I haven't got it right yet. Pastel pencils work much better with darker papers. The Jimmy Cagney drawing in my gallery is on black pastel paper. Best of luck look forwards to seeing your picture.