Shape: positive and negative: positive shape is the totality of the mass lying between its contours; in three-dimensional work, the visible shape or outer limit of a form changes as the viewer's position is changed. These outer limits are seen as shapes moving back and forth between major contours. Negative space is empty space defined by positive shape. Sometimes referred to as occupied and unoccupied space.
Chihuly created a spectacular site-specific installation entitled "Chelsea Persians" featuring over one hundred Persian blown glass elements which are open, disc-like forms with striations (called “body wraps”).