Khachkars ("Խաչքար" in Armenian, literally meaning "cross-stone") are a uniquely Armenian form of art, which evolved into incredibly ornate form which reached its peak in the 12-13th centuries.
Khachkars are most commonly used as tombstones, but were sometimes used as memorials. The biggest khachkar cemetery in Armenia is the Noratus Cemetery, while the biggest in the world is in Jugha, in Nakhichevan.
Most khachkars do not depict Christ on the cross, but a few notable exception except. Most khachkars fall under the basic definition of a cross carved onto a stone. A few of the highly detailed and elaborate khachkars are called "lacework" khachkars. Khachkars which are freestanding crosses are called tevavor or "with arms" khachkars. Finally there are some examples of totem-pole style khachkars. The cross is usually the standard Armenian cross with two triple-loops on each arm of the cross, but can be simpler or vary.
Well over 95% of khachkars fall into this category. They are widely distributed across Historic Armenia and are now making their way into Diaspora communities as well as an export from Armenia for contemporary tombstones.
During one of my trips to Goshavank a guide noted that the holes in the bottom center of this particular Khachkar, and at each of the 4 points of the Khach (cross) once were the seats of 5 large, brilliant and beautiful diamonds. The story went that many across the Caucusus had heard of these diamonds and when word reached Tamerlane on one of his regional campaigns, he immediately came and dug them out of this stone, and they were never seen again. - Hovaness Avedyan (2006)