It's been a long time since I last made a drawing, but here goes! This drawing represents a customized Vajra (or Dorje in Tibetan), which is the sanskrit word for Lightning bolt and also diamond.
It is a short metal weapon that has the nature of a diamond (it can cut any substance but not be cut itself) and the nature of the thunderbolt (irresistible force).
There's a whole explanation of what this Buddhist symbol stands for, but I'll kindly refer to Wikipedia for additional information. In short: when worn in a pendant it reminds the viewer and wearer to the supreme indestructability of wisdom and it destroys ignorance. And yes, I have one as a pendant. Also: it represents the male principle (the Bell is the female one).
So I customized it and added a Dharma wheel in the middle, because I think it adds a little something to the whole.