From the artist's site:
"Rolex Time sand is packed in 30 kg bags . Each bag's content equals 30 days flowing in a standard hourglass. On the 18 pallets, there are 972 bags with a total weight of 29.160 Kg. They last for 81 years- our generous estimation of an average lifetime."
Another piece, called One Billion Dollars...
If you are a vinyl afficionado, you will also dig Marcovici's execution of Turntable Pilot - a radio controlled USB camera mounted to the tone arm of a turntable that allows the DJ to fly in over the grooves of the record and tuch down with precision on command.