Crystal City

Another idea that came from my high school years, where I spent almost all of my classes drawing and writing instead of listening because I had no patience.  I'm still an awful listener.

The capital city is built around a huge crystal meteor. The people worship this glittery rock and guard it feverishly, believing the shard to be a physical projection of their god.

The crystal is harder than any known tool. Many ignorant thieves who wanted to pocket a bit of wealth ended up returning empty-handed. If they by chance managed to escape from the righteous wrath of the city guards, that is.