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The main disadvantage that you will be dealing with when you work with black or white is high contrast. This is more likely to be a problem with black than with white. Cameras may sometimes over-compensate for black backgrounds, resulting in an overexposed lighter-colored object on top—your jewelry. This problem is less likely to occur with white backdrops, but you still may find that your jewelry items on white displays under-expose.

For this reason you may not want to use the same rules for displaying your jewelry in photographs as you would if you were displaying it in real life. In real life most people would want to aim for contrast—bright or light-colored jewelry on black, darker-colored jewelry on white. But in a photograph, darker-colored jewelry may actually show up better against black, and lighter-colored jewelry may show up better on white. Do some experimentation to find out what works best for you. You may find that if you stand back a bit from the piece when you take your shot, and include another background behind the display, the photos expose more evenly.