Short glassworks with thick round shapes, like bowls, are usually photographed with light coming from under the object. A light box for viewing transparencies can come in handy. Arrange the objects on the light box and place a second light over them to fill the shadows on the portions facing the camera.
To get the right exposure for this setup, take a reading on the light box and open the aperture setting by one and a half stops.
Adapted from Photographing Arts, Crafts & Collectibles by Steve Meltzer (Lark Books, 2007, $25)