I have a quantity of nice walnut that is nearly entirely heartwood. It seems that most woodworkers desire this even, darker wood for finishing. I, however, like the nice contrast of a streak of bright sapwood through the piece.

Can a someone suggest a method of adding a “splash” of sapwood type color through the existing dark walnut? I’m planning on finishing with a tiny bit of heavily diluted orange dye to warm it overall then an oil based topcoat.