This prabha is quite exceptional, both for its sophisticated iconography and its craftsmanship [1]. At the apex, there is a flaming pointed arch enclosing a three-pronged vajra. The vajra is an extension from the flames which surround the deities in the lower section of the prabha. A round nimbus surrounds a Bodhisattva who appears to be a four-armed form of Vajrapani, identified by the large vajra held in his raised right hand. His lower right hand touches his right hip. His two left arms are positioned together up to the elbow, then one hand touches the knee with palm held down; the other hand cannot be seen but the forearm is visible at the elbow joint. Vajrapani wears a three-panelled triangular crown, but no necklaces or earrings. He appears to be naked to the waist, with well-developed chest muscles, and he is seated, wearing a dhoti with voluminous folds, on a lotus pedestal.
While the outer edges of the prabha simply have floral scrolling, there is an interior arch, within which four additional Buddhist deities are portrayed. To the immediate right of Vajrapani is an emaciated male figure, with his ribs showing, matted hair (with a 'feather' in the hair), and a long beard. His left hand is pendant and now worn; the right arm is also hanging but appears to hold an indeterminate object. He appears to be sitting on an animal, whose haunch and bent leg are clear, but the animal's head is hard to distinguish. Below, another thin male figure, apparently nude save for the 'feather' in the hair, and without a beard, holds a jewel in his raised left hand. He appears to be seated on a rock. The identification of these two figures remains uncertain, but they may perhaps be yogins.
To the left of Vajrapani, the female wrathful deity Lhamo is recognisable, from her emaciation and the trident club raised in her left hand. She wears no crown or earrings. She is nude, with pendant breasts, and seated in lalitasana. She has scarves visible to the left. Beneath Lhamo, there is a male figure holding a chopper in his raised right hand and a skull cup in his left, dancing on the tip of one foot, balancing by raising his other foot very high. He wears a crown composed of three triangular panels pulling his hair into a chignon behind the crown. This appears to be a form of Heruka.
The centre of the convex panel is open, for this is where the principal deity would have been represented. With such an entourage, it is doubtful that the deity would have been Sakyamuni; instead one may tentatively suggest Akshobhya, as the lord of the vajra family which comprises many wrathful deities. The identification of the figures is complemented by the mantras which appear on the lower lateral panels, incised in the Tibetan alphabet. At the right, we read: Om'tsa na ra'ma ha ro sha na hu phat. This is the well-known mantra for the protective deity Acala. In the left panel appears the syllable bhyo, evidently the root syllable for the deity Lhamo, followed by the mantra for Lhamo [2]: Om dru dru ro ru tsa pa la a (two letters effaced) mra hrum bhyo dza dza.
The prabha is solid cast, and its reverse is plain with almost no finishing. It is very unusual for its combination of scrollwork, deities and human figures, the incised mantras, and above all the distinctive style of the lithe bodies with thin waists, full chest, and highly exaggerated leg poses of both the yogin figures and wrathful deities. By their movements and body proportions, these figures recall the narrative scenes of the lintels of the Lhasa Jokhang [3]. Their diminutive size also recalls miniature deities popular in late Tang China. However, the dynamic quality of their movement is completely removed from the benign attitudes of Chinese Buddhas and Bodhisattvas. This vitality corresponds to Tibetan design taste as known from metalwork of the imperial period. The prabha is also reported to have been found in Tibet. In view of the existence of Tibetan translations of rituals for Lhamo, Heruka, and Vajrapani in the late eighth to early ninth century, a ninth-century dating for it may be tentatively suggested.
[Footnotes:]
1 A prabhamandala, literally a 'circle of brilliance', is a complete backplate for a Buddhist icon; the term refers to the special aura which emanates from Buddhist deities. As an abbreviation, it is commonplace to refer simply to the prabha instead.
2 I thank Dr Robert Mayer of the Oriental Institute, Oxford, for this information.
3 See Introduction, fig. 8.