Polyhedral Agate.  
A very rare variety of agate/quartz.
Found in the mid 1970s in Paraiba, Brazil
It is thought that they formed in the cavities between large crystals of angel wing calcite.
These have not been mined since the 70's, so pretty hard to come across.
 
So delicate and luxurious...Could make this into a pendant. would look stunning...
The Orange pop with the black is divine...
Two sides polished on this specimen so you can see its full beauty! 

Weight 
26 gram
Measures 
9cm x 2cm x 0.5cm approx.

Metaphysics
I can only speak for myself; I have had a large one with big cavity on my altar for couple of weeks now...it creates another portal, I feel, that takes me where I wish to journey...Im having some profound experiences...