Tsa Tsas [Tib.: ཚ་ཚ་] are relief style imprints, made from a mixture of clay and precious jewel-substance in molds of metal, potter's clay or wood.
When the Tsa Tsas act as filler for stupas, ash or bone remains of deceased masters are added as a special blessing. Before the Tsa Tsas are to be used to fill a stupa, they are baked or allowed to dry in the open air and sometimes, painted with mineral pigments.
Traditionally in Tibet, tsa tsas were placed inside caves in the Himalayan mountains or inside the stupas. But special Tsa Tsas were also found in monastic devotional rooms and on private home altars
Throughout the centuries, the various traditions diversified Tsa Tsas into hundreds of different forms and sizes.
Currently you can find 53 different Tsa Tsas here. Some are found frequently, others - primarily the several hundred years old ones - are exceptionally rare. It is quite common that centuries-old Tsa Tsas completely or partially lost their original ornamental painting. Overtime these Tsas Tsas, therefore have frequently developed a very interesting patina.