Images in which the subjects appear highly respectable, like a proper gentleman or lady. Or show a beautiful display of grace.
Common traits of those depicted include formal clothes outfits, Victorian attires, done-up hair, calm and/or neutral expression, monocles, mustaches, top hats, walking canes, cups of tea, a curved smoking smoking pipe, and maybe even a British accent.
Stage magicians, while likely possessing many of these qualities, do not automatically apply. It is especially desirable if the subjects who appear are not normally depicted in such a manner, but those who are well-known for their Gentlemanly honor, such as Dudley from Street Fighter, would apply just as equally.
Alternately, for elegance, those who give off a graceful air about their actions, such as a curtsy, a demonstration on a violin, piano, or other high-class instrument, or even a wink. This doesn't have to be restricted to what they wear, but how they act, and their poise.
Extra points if the image also has elegance in artistic levels. This doesn't simply mean "good art", but is more about creating a graceful atmosphere by manipulating the lighting, shading, color palette and etc. Such as post #3836466, post #5539237 and post #5413350.
Not to be confused with World of Elegance, Urd's angel from Aa Megami-sama (for whom this pool was named).