In order to build minerals the atoms must join together. The process of the joining of atoms is called bonding. Ionic Covalent Figure for NaCl.
All atoms attempt to achieve the stable configuration of eight electrons in the outer most shell.
To do this they can gain or lose electrons. Ionic bonds are generally weak and many of the compounds resulting from these bonds are soluble in water. Covalent bonds result from the sharing of electrons. See the Cl-Cl Figure . Each chlorine shares one of its outer most electrons with an adjacent chlorine atom.