Chemical element of an element to exist in one of many structural forms is known as 'allotropy'. The standard state, also known as the reference state, of an element is defined as its thermodynamically most stable state at a pressure of 1 bar and a given temperature (typically at 298.15 K). In thermochemistry, an element is defined to have an enthalpy of formation of zero in its standard state. For example, the reference state for carbon is graphite, because the structure of graphite is more stable than that of the other allotropes. Several kinds of descriptive categorizations can be applied broadly to
Red diamond of the diamond and is largely what determines its value. The next most important attribute is the diamond’s carat weight, followed by its clarity, and cut. The color in red diamonds is assessed according to its hue and saturation. Red diamonds can occur with secondary colors, such as brown-red, orange-red, or purple-red, but red is not a modifying color for any other diamond color. Additionally, red diamonds never appear with a tertiary modifying color, as is the case in other diamond colors. A pure red diamond is ideal but an even rarer find than a red with a secondary color.