Formation and Nature of Pearl: Pearl is secreted by the mantle of the pearl oyster as a protection against foreign objects which may be sand particles, minute larval forms or other such things. To study the mode of formation of pearl it is essential to know the structure of the shell and mantle.
Carbonite is a cloud-based solution optimized for individuals and small businesses seeking secure offsite system backups, which will protect them in the case of a disaster. Large corporations can pretty much afford private cloud systems for backup and subsequent disaster recovery efforts.
Cementite, also known as iron carbide, is a chemical compound of iron and carbon, with the formula Fe 3 C (or Fe 2 C:Fe).y weight, it is 6.67% carbon and 93.3% iron. It has an orthorhombic crystal structure. It is a hard, brittle material, normally classified as a ceramic in its pure form, though it is more important in metallurgy.