Optimal facet placement is the key to brilliance and more important than facet patterning. Above and below each vertebra are joints called facet joints. The rear facet of the centrum is strongly concave. Brilliance refers to the white light reflections from the external and internal facet surfaces. Affect display is a critical facet of interpersonal communication. The tapered structure leads to a reduction of the power density at the output facet. Each individual facet is a Fresnel lens. The apex is directed downward and presents an oval facet for articulation with the coccyx. These officials had specific responsibilities concerning every facet of life within the Inner Court. Its influence stood behind and shaped every facet of public life. Astrology remains an important facet of folk belief in the contemporary lives of many Hindus. Medicinal use is one important facet of psychoactive drug usage. Sex constituted only a facet of the courtesan's array of services. Each style represented a specific facet of Blige's life. Education is another important facet of Saint-Louis.