In the khachkar composition the cross appears as its main component, and the remaining elements assume ideological value through their position and connection to the cross. From the early middle ages, the khachkar composition acquired for the first time the cross with off-centered arrangement (as opposed to chi-ro), filed with vegetative components cross. In the 9-10th centuries the cross wings are capped with double buttons, then receive a form of chamomile, rosette, lily or palm decor. In the process of cross formation the twin buttons become trebled. In the 11th century, together with the fact that the composition and the cross becomes netted, the middle button of trilobed ends of the cross stretches and acquires the form of flower bud or symmetric decor - giving a blossoming, vegetative appearance to the cross. This remains the main type of the central cross up to 18th century. The crossing point is presented as a source of light and becomes a point of emphasize by means of a gem. But the depiction of the "illuminated cross" was "shadowed" by the presentation of the cross as a tree of life, and only had the single expression emphasizing the solar-illuminating advent of the cross and Christ. Khachkar compositions also frequently appear with crosses placed on the cornice, in the section of rosette, and the edges of the belt. The cross is one of the more movable elements of the composition. One of the principal differences of the khachkar composition from the early medieval cross compositions is the fact that the khachkar encloses the cross into a niche - visibly indicating its worshiped and holy status. The further "altarization" of the cross in 11th century led to the emergence of the walled khachkars, by which the niche received also an architectural solution emphasizing, even more, the worshiping element. Beginning in the 11th century, the cross and the niche are mutually corresponding. As a result, in several khachkars of the 12-14th centuries the niche through its contours tries to mirror the outline of the cross, becoming like a container of the cross. Since the early khachkars lacked cornices, the niche in these compositions not only presented the ritualistic character of the cross to the believer (e.g. worshiping), but also symbolized the terrestrial sphere, and the abstract-universal measure of the cross. Later, with the increase of the perception of the cross as a holy mediator, the cornice takes on the connotation of the terrestrial sphere, and the niche, just like the cross, becomes a sort of middle ring between the cornice and rosette (between the top and bottom parts as a whole).
The illuminate symbols in the khachkar composition were placed at the top of the niche or on the cornice, and referred to two main themes: the crucifixion and Second Advent of the cross. The sun and the moon were depicted, and sometimes even a star. The sun is depicted more decorated than the moon or the star and sometimes the moon is portrayed in a form of crescent. In the "All-savior" khachkars, the sun and the moon are given a human form, and are depicted mounted on an eagle and bull respectively.