You don't say whether you are using the Nikon 1 J1 or Nikon 1 V1 nor which lens you are using.
None of the current (July 2012) Nikon-1 lenses are macro lenses although you can use the FT1 adapter with Nikon-F lenses to get true macro capability.
However you should be able to get reasonably good close-up photographs of jewelry using the J1 or V1 and one of the standard kit lenses - I imagine most people have the 10-30mm lens.
If you have the Nikon-1 J1, I wouldn't use it's built in flash for very close subjects, the lens may mask the subject when used close up. I'd try and get a good source of lighting such as a window on a sunny day, I'd use a reflector to bounce light onto the other sides of the subject - a sheet of white paper will work.
If you have the 10-30 mm lens, I'd set it to 30 mm, you'll need to move the camera a little further away from the subject but the subject will fill more of the picture (this depends on the lens, experiment, don't assume that macro means getting the lens as close as possible to the subject).
Using any sort of tripod or camera support (even improvised) will help a lot, use the timer to set a delayed release.
Depth of focus
If some parts of the object are not in focus, I'd select "single-area" focus mode and position the focus area on the most important element of the object. If necessary set exposure mode to P or A and adjust the aperture settings by using the zoom lever so that the camera is using a smaller aperture (try F8 or F16 and compare results).