A crux gemmata is a form of cross typical of Early Christian and Early Medieval art, where the cross, or at least its front side, is principally decorated with jewels. In an actual cross, rather than a painted image of one, the reverse side often has engraved images of the Crucifixion of Jesus or other subjects.

The Christian cross, seen as a representation of the crucifixion of Jesus on a large wooden cross, is a symbol of Christianity. It is related to the crucifix and to the more general family of cross symbols, the term cross itself being detached from the original specifically Christian meaning in modern English.