It's possible the oil used in the stain or the finish on it has aged and darkened. This especially happens with shellac. You can achieve the color but not the dry look of the entire finish. Then how you go about duplicating the color would depend on the kind of wood you are finishing. With some species of wood which has very pronounced soft and hard grain if you just apply a dark stain it will end up with a very stripped look. You may need to put a thin sealer on the wood and use a gel stain to subdue this. A gel stain is closer to being paint than stain and will tend to cover up the grain of the wood.When I look at old European stains (approximately 1800's to 1950) I often notice a distinct difference. They often have a very dark and less translucent pigment. I attached a photo to demonstrate an example of what I generally mean. I want to replicate this on a piece of furniture I'm building but I really don't know what they were using. Does anyone have any information on what was used for this type of stain, or if nothing else, a modern product that comes close?