Annie Sloan, the other chalk paint brands and the major refinishing brands all sell a version of dark wax. Dark wax is essentially a faux finishing tool that allows you to add an aged-look to a newly painted piece. Used on the right piece or in the right places, it is very effective; however, it can also be a disaster and may end up giving the piece a dirty, streaked look.
I have used it quite a few times but I have to say that I prefer it on carvings, distressed edges and darker colours. I would never put in on Pure White or Old White unless I was really trying to make the piece look old, like something that had been painted years before and aged. This is the second piece of furniture that I painted when I first started out. It is in AS Provence and you can see that it is a lovely mahogany dresser to begin with. I plunged right in and put the dark wax on the drawers, the edges and the top. I ended up removing some of it because it was streaky but I did leave a lot on. This is one of the pieces that people comment on the most and I did have someone ask me if it was actually very old or just made to look that way. So the wax did its job.
I tend to use dark wax mostly on distressed edges. These pix show it on the carved trims:
If you are afraid to use it, I would suggest you start out in small areas and not try to put it on a large surface until you are comfortable with the process. There are some basic rules to using it: Put it on over a clear wax because it contains stain and will sink into the paint and be impossible to remove if you don’t like it. If I distress something, I always use a bit of dark wax to make the wood stand out. Mix a bit of varsol in with the wax to thin it out if you find it hard to work with ( this also makes a good glaze). You can also remove it if you don’t like it. Clear wax will take if off but the cheaper, more efficient method is to use solvent ( varsol).
One of the things that I like the best about dark wax is the way it deepens colours. This little antique dresser was painted in red chalk paint. I waxed it then put dark wax over the whole thing. It settled nicely into the edges, the distressing and enhanced the colour. Because it is an antique farmhouse dresser, it really seemed to suit the piece. I also used it on the knobs to make them match in colour and to age them as well.
Dark wax, glazes and washes all give more dimension to painted furniture.