When I first saw the concept renderings, I thought I was looking at a diamond perched upon a hill.  To the contrary, the images show a new mixed-use sustainable tower concept, or "ecological tower," by Foster + Partners for Khanty Mansiysk, Siberia.  The tower rises on the foundation of two podium buildings, each diamond-cut in style to allow light to penetrate the atrium.  The apex of the tower will have a panoramic viewing platform and restaurant for guests to gaze out into the city.  Paramount to the design is the desire to facilitate solar gain (it’s cold in Siberia) and allow natural lighting.  Encompassed by a densely wooded area, the architects designed the building to minimize disturbance to the landscape. 

Good Links:
++Designs Revealed for New Ecological Tower in Siberia [Foster + Partners]
++Siberia’s Sparkling Eco Tower [WAN]