Hey all, most dark stains like "mahogany" and "dark walnut" require several applications of the stain in order to arrive at the desired depth of color. It's important to let each progressive layer dry about 4-5 hours or until the stain no longer feels "tacky" and doesn't leave any residue on a clean rag. As far as gel stains go, they are just stains with a little more body, Minwax has a line of these, but it's use is really for vertical surfaces (doors, cabinets, etc.) to reduce running and dripping onto surfaces you don't really want the stain on. Its gel characteristics don't normally assist on coverage. Sometimes, although rarely, a topcoat (varnish) can soak in through a previous stain, just as crisn said. This has to be removed with sanding, starting with about a 60 or 80 grit, and moving to a 120. For a really great finish you should end with a 220 grit. Finish with 2-3 coats of a quality semi gloss polyurethane. Same rule between coats as the stain, but make sure to sand with a 600 sand wet sand paper in between coats. Hope this helps all you mantle refinishers!