Atom Definition. An atom is the defining structure of an element, which cannot be broken by any chemical means. A typical atom consists of a nucleus of protons and neutrons with electrons orbiting this nucleus. However, an atom can consist of a single proton (i.e., the protium isotope of hydrogen) as a nucleus.
Mosaic art flourished in the Byzantine Empire from the 6th to the 15th centuries; that tradition was adopted by the Norman kingdom in Sicily in the 12th century, by eastern-influenced Venice, and among the Rus in Ukraine.osaic is an art form which uses small pieces of materials placed together to create a unified whole. The materials commonly used are marble or other stone, glass, pottery, mirror or foil-backed glass, or shells.
Almost 10,000 years later, as settled communities were established, tiles were manufactured in Mesopotamia and India. The first use of functional pottery vessels for storing water and food is thought to be around 9000 or 10,000 BC. Clay bricks were also made around the same time. Glass was believed to be discovered in Egypt around 8000 BC, when overheating of kilns produced a colored glaze on the pottery. Experts estimate that it was not until 1500 BC that glass was produced independently of ceramics and fashioned into separate items. Fast forward to the Middle Ages, when the metal industry was in its infancy.