In 2003 ownership of Rolls-Royce plc was passed to Rolls-Royce Group plc incorporated 21 March 2003 which issued its own new shares for payment to the previous shareholders. In 2011 in the same way Rolls-Royce Group plc passed ownership on 23 May 2011 to Rolls-Royce Holdings plc a wholly new company incorporated 10 February 2011. Rolls-Royce plc remains the principal trading company. Rolls-Royce Holdings plc, like its immediate predecessor, is merely a holding company.
1 Crimson = 1.1 tons (2200 lbs.) per cubic yard. 2  Rock (57 & 89) = 1.2 tons (2400 lbs.) per cubic yard. 3  Lime Rock (919) = 1.25 tons (2500 lbs.) per cubic yard.  River Rock (all) = 1.325 tons (2650 lbs.) per cubic yard.
General Weights. Solid rock is estimated at 2.5 to 3tons per cubic meter. If rock is crushed into uniform sizes, the presence of open space between the particles causes the load to be lighter -- approximately 1.6 tons per cubic meter.ixed sizes of crushed rock can range from 1.6 to 2.2 tons per cubic meter. Weighing in at .92 tons are masonry sand, building sand, and stone chips or flakes. These are some of the lightest materials. The next level, at just under one ton, are concrete sand and airfield sand.