This type of crown is reserved for spiritual masters of Buddhism (lamas) during special initiation rituals. The figures represent the Five Transcendent Buddhas who personify the five kinds of wisdom in Vajrayana Buddhism.
“Diadem,” late 19th or early 20th century, Tibet
Figure 1: Amitabha (red)
Figure 2: Amo ghasiddhi (green)
Figure 3: Vairochana (white)
Figure 4: Ratnasambhava (yellow)
Figure 5: Akshobhya (blue)