Special items of the hierarchical service are the dikerion and the trikerion. These are two hand-held, ornamental candlesticks in which two (dikerion) or three (trikerion) candles are placed. The use of the dikerion and trikerion at the patriarchal liturgy began in the twelfth century.  Originally these candlesticks were ascribed only to kings and patriarchs (and not to all bishops) as they were perceived as attributes reflecting the dignity of teaching. This is mentioned in the twelfth century by Theodore Balsamon, the patriarch of Antioch, who insisted that the right to bless the faithful with candlesticks belonged to kings, patriarchs, autocephalous archbishops of Bulgaria and Cyprus, and also a few metropolitans to whom the kings had given this right. 
Later the dikerion and trikerion came to be used by all hierarchs at church services. The trikerion is interpreted symbolically as an indication of the three Persons of the Holy Trinity, while dikerion indicates the two natures of Jesus Christ.  Candles placed in the trikerion and dikerion may be connected at the top in such a way that a single flame is formed. A more common style has crossing candles whose top ends are directed in different directions. 
 Jacob, “Le chandelier a trois branches de l’eveque Pantoleon: A propos de l’inscription de Geroges de Gallipoli,” Bolletino della Badia greca di Grottaferata 53 (1999), 187-199.
Theodore Balsamon Reflections, PG 138, 1016D-11017C.
Simeon of Thessalonica Concerning the Holy Temple 59, 61. PG 155, 721BC.
 Deacon Mikhail Zheltov, “Dikirion” in Orthodox Encyclopedia, vol. 14, 693.