I've often seen questions on various forums about coloring faux-ivory single action revolver grips and everyone says it can't be done. I just colored a set of Ajax polymer white grips using a solution of 99% Isopropyl Alcohol and common grocery store spice Turmeric. This results in a bright yellow color which seems to stick very well (I haven't chalenged it with solvents and oils yet). (BTW -- don't get it on your hands or clothing.) By diluting the solution one should be able to arrive at the degree of antiqueing desired. Degrease thoroughly, maybe go over the grips with super fine crocus, and have at it. Let me know your results.

I recently saw an ad by a company that will dye an entire new HK gray rifle to black or dark green. I wouldn't have thought it possible, thinking the color was molded in and permanent. I guess it just shows that sometimes it pays to try some things for yourself, rather than listening to "conventional" wisdom!

This is in fact an old woodworking trick to dye wood. Soak rusty nails in vinegar for a week and the resulting foul juice turns oak into fake ebony! Hit oak (or any wood with a high tannin content) with ammonia liquid or fumes to darken it (the process works a while longer after you stop so stop before it gets to the desired color). I think the back of the Dixie Gun Works catalog lists a bunch of wood and metal coloring formulas. Remember that water based dyes will raise the grain of the wood so you'll have to sand and reapply a couple of times. Not much of a problem with alcohol and other solvents.