a Buddhist "thunderbolt" and "diamond" ritual object,

https://templearchitecture.blogspot.com/2006/11/sacred-object-thunderbolt-diamond.html

Supreme indestructibility of knowledge: Dorje can also refer to a small sceptre held in the right hand by Tibetan lamas during religious ceremonies. The vajra destroys all kinds of ignorance, and itself is indestructible. In tantric rituals the Vajra symbolizes the male principle which represents method in the right hand and the Bell symbolizes the female principle, which is held in the left. Their interaction leads to enlightenment. Also the Dorje or Vajra represents the "Upaya" or method Tibetans name Vajra as "Dorje". Made to be worn as a pendant, it reminds the wearer, and the viewer, of the supreme indestructibility of knowledge. In Buddhism the vajra is the symbol of Vajrayana, one of the three major branches of Buddhism. Vajrayana is translated as "Thunderbolt Way" or "Diamond Way" and can imply the thunderbolt experience of Buddhist enlightenment or bodhi and also implies indestructibility, just as diamonds are harder than other gemstones.

Theres more at the link. Interesting.