Period 2 element a supplement for the prevention and treatment of osteoporosis and arthritis. Carbon is the chemical element with atomic number 6, occurring as C, C and C. At standard temperature and pressure, carbon is a solid, occurring in many different allotropes, the most common of which are graphite, diamond, the fullerenes and amorphous carbon. Graphite is a soft, hexagonal crystalline, opaque black semimetal with very good conductive and thermodynamically stable properties. Diamond however is a highly transparent colourless cubic crystal with poor conductive properties, is the hardest known naturally occurring mineral and has the highest refractive index of all gemstones. In
Anisodesmic crystal anion equals the charge on that anion." When there is more than one type of bonding in a crystal, strongly anisotropic physical properties can result such as those of graphite. Many other substances have anisotropic physical properties. Such properties are directly related to the atomic structures of the substances. Conversely, halite is an example of an isotropic crystal with equal hardness in all directions. Anisodesmic crystal An anisodesmic crystal (sometimes anisodemic crystal) is a crystal containing bonds with differing electrostatic valencies. All other crystals are known as isodesmic crystals (or isodemic) and examples include diamond and halite. These terms are