Describe the appearance of the man in the doorway in "After Twenty Years." How do his possessions help you understand his economic condition?

The man in the doorway has a pale, square-jawed face with keen eyes and a little white scar near his right eyebrow. These details hint at his criminality. In the very next line, we're told that he's wearing a large diamond scarf pin, oddly set. The fact that he's wearing a diamond, and such a large one at that, indicates that the strange man in the doorway must be quite well-off. Our initial impressions are confirmed when the man pulls out a handsome-looking watch, its lids set with small diamonds.
However, note the crucial detail about the diamond scarf pin: that it is "oddly set." This would appear to suggest that, for all his wealth, the man doesn't quite know how to wear it properly. Again, this nugget of information provides us with a clue as to the man's status as a criminal. He certainly wasn't born into money.