The coloring comes variety of organic compounds called conjugated dienes, that reflect visible light in both the high and low end range of the visible spectrum (from 400-700nm). Some of which have solubility in polar protic compounds like water, others of which are only soluble in organic solvents.
That’s where the magic of acetone comes in. It is highly polar, but it is non-protic, therefore it dissolves them all. And by dissolving them, they work their way to the surface and bring all of their bright beautiful purple color with them.
The ultraviolet rays from the sun then do their part and kick off the first oxidation reaction to finalize the effect.
But don’t store your piece in the sun. Further oxidation will result in chemical changes leading to brown. And nobody wants brown Purpleheart.
Follow these steps for best results:
1) finish sand your piece.
2) wet with acetone thoroughly
3) set piece in full bright sun
4) flip piece every 30 min.
5) re-wet with acetone each time you flip
6) repeat cycle for 3-4 hours.
7) let piece rest indoors for an additional day or more before finishing. (Oxidation is continuing)
8. seal thoroughly with top coat of choice. (Mine is lacquer) about 4 coats
9) put UV protectant over that (ie spar urethane, to keep your purple color. (Stops further oxidation)