altarpiece

 An altarpiece is an artwork such as a painting, sculpture or relief representing a religious subject made for placing behind the altar of a Christian church.

 

Festoon

A Festoon (from French feston, Italian festone, from a Late Latin festo, originally a festal garland, Latin festum, feast), is a wreath or garland, and so in architecture a conventional arrangement of flowers, foliage or fruit bound together and suspended by ribbons, either from a decorated knot, or held in the mouths of lions, or suspended across the back of bulls heads as in the Temple of Vesta at Tivoli. The motif is sometimes known as a swag when depicting fabric or linen.

Gemology

Gemology or gemmology is the science, art and profession of identifying and evaluating gemstones. It is considered a geoscience and a branch of mineralogy. Some jewelers are academically trained gemologists and are qualified to identify and evaluate gems.