Lava is made up of crystals, volcanic glass, and bubbles (volcanic gases). As magma gets closer to the surface and cools, it begins to crystallize minerals like olivine and form bubbles of volcanic gases. When lava erupts it is made up of a slush of crystals, liquid, and bubbles. The liquid freezes to form volcanic glass. Chemically lava is made of the elements silicon, oxygen, aluminum, iron, magnesium, calcium, sodium, potassium, phosphorus, and titanium (plus other elements in very small concentrations. Have a look at the background information in Minerals, Magma, and Volcanic Rocks.
The HoverJack has a weight limit of 1200 lbs. When lifting a heavy patient, extra caution must be taken to center him or her properly on the HoverJack. partners
I have a set of Ultegras and Zeros, and the cleat assembly on the Zeros seems a lot heavier than the Ultegras. Last edited by 2wheel-lee; 07-16-2007 at 12:20 PM. The 6.8kg weight limit on a bike imposed by UCI, does it include pedals and cages? Why do people usually measure the weight without the pedals anyway? I know that everybody rides with different pedals, but on a per-bike basis for one rider, wouldn't there be just one set of pedal that this specific rider prefers?