Dyckia lindelvaldeae
If a diamond had leaves it would be something like this here.
This Dyckia species is not dwarfed by any means it is so naturally.
This fits roominly within your right hand.
What a perfect plant for that sunny windowsill!
Dyckias go from two meters across gigantic crowns to babies like this and even smaller.
Native to Central Brazil Cerrado its flowers are scented and the plant needs another one to produce seeds as it is not self fertile.
..and better yet, as Diamonds they are forever too.