The pore spaces (known as vesicles) in pumice are a clue to how it forms. The vesicles are actually gas bubbles that were trapped in the rock during the rapid cooling of a gas-rich frothy magma. The material cools so quickly that atoms in the melt are not able to arrange themselves into a crystalline structure.Thus, pumice is an amorphous volcanic glass known as a  mineraloid .he abundant vesicles in pumice and the thin walls between them give the rock a very low specific gravity. It typically has a specific gravity of less than one, giving the rock an ability to float on water.
While an electromagnetic wave is called just a disturbance, a mechanical wave is considered a periodic disturbance. Mechanical waves are also called elastic waves as their propagation depends on the elastic properties of the medium through which the waves pass.
Best Answer: 1.A mechanical wave is a wave that requires a medium through which to transmit energy. Sound waves, waves in a Slinky, and pressure waves are all examples of this.Sound waves need air molecules in order to exist; the Slinky waves need the Slinky, and the waves in the ocean need the water.nce this initial energy is added, the wave will travel through the medium until all the energy has been transferred. There are three types of mechanical waves. Transverse waves are waves that cause the medium to vibrate at a 90-degree angle to the direction of the wave.