There are a few variations of mahogany. Red, brown, and reddish-brown

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I've been involved in furniture building for a number of years, and the toughest job I've encountered is trying to match a certain color. Lighting, age of the piece and "proprietary" stains used by the manufacturers all conspire against an easy color match.
There are touch-up kits out there, but if you're doing more than just scratches, you may be better off re-doing the entire piece. Maybe try some oil-based Watco natural? Caution, it'll smell for awhile.
P.S.- Be careful with those oily rags.