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.umice is produced in two forms: rock pumice and pumicite. Pumicite is a name given to very fine grained pumice (less than 4 millimeters in diameter down to submillimeter sizes).
Post and lintel construction is recognized by its simple vertical and horizontal design, in which a pair of vertical supports are set in the ground or a foundation, and a horizontal structure is balanced on top of them.
It is the largest ancient temple complex in the world, and represents the combined achievement of many generations of Egyptian builders. Karnak actually consists of several temples. One of most famous structures of Karnak is the Hypostyle Hall, a hall area of 5,000 m2 (50,000 sq ft).