Large Voids
Ceramic Chip Capacitor Large Voids - Application Note 2417

Sample & Method
A multi-layer ceramic chip capacitor bulk scan image.
Result
Voids between plates in ceramic chip capacitors are typically circular or nearly circular, but one type is elongate, as seen here. Often times they are wiggly shaped. These voids are thought to originate as airborne fiber particles. During firing of the ceramic, the particle itself is consumed, leaving a characteristic elongate void.