This very distinctive bonsai belongs to Mauro Stemberger. The rock was made by Erik Križovenský, a master of unique pots and other creative vessels for planting bonsai. No mention is made of the type tree, but it looks like some type of Juniper. I cropped Mauro's original photo (below) to get a closer look and to eliminate some background noise

It’s past due time to revisit Mauro Stemberger, an old favorite here on Bark. If you’d like to see more of what Mauro is up to you can visit him on facebook and on his Italian Bonsai Dream website. You can also visit Erik Križovenský (the artist who made the rock), on his website and on facebook. –

Hanging off a cliff somewhere in the Alps with its disappearing live vein and deadwood bones

Erik Križovenský is a whiz when it come to unique pots and other vessels for planting bonsai

A piece of Mauro's balcony bonsai collection

Maruo's T-shirt and bookThe original photo