This ritual implement is called a jeweled vajra as both ends are in the shape of a flaming jewel. Together with the single-pronged, three-pronged, five-pronged, and stupa-toped versions, it forms a set of five types of vajras, known as goshusho in Japanese. As remnants of pigment can be seen on the lobes of the jewels, it has been surmised that each lobe was painted a different color. 
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