I have created this piece using Smokey Quartz 2.5 cm crystal tumble stones.  And it is stunning!

Smokey Quartz is an excellent grounding stone.

Smokey Quartz disperses fear, lifts depression and negativity. It brings emotional calmness, relieving stress and anxiety. Promotes positive thoughts and action, and alleviates suicidal tendencies. Dispels nightmares and manifests your dreams.