Garnet not like sapphire blue in subdued daylight but more reminiscent of the grayish blues and greenish blues sometimes seen in spinel. However, in white LED light, the color is equal to the best cornflower blue sapphire, or D block tanzanite; this is due to the blue garnet's ability to absorb the yellow component of the emitted light. Pyrope is an indicator mineral for high-pressure rocks. The garnets from mantle-derived rocks, peridotites, and eclogites commonly contain a pyrope variety. Spessartine or spessartite is manganese aluminium garnet, MnAl(SiO). Its name is derived from Spessart in Bavaria. It occurs most often in granite
Diamond (gemstone) reflect and refract light. In addition to carrying the most importance to a diamond's quality as a gemstone, the cut is also the most difficult to quantitatively judge. A number of factors, including proportion, polish, symmetry, and the relative angles of various facets, are determined by the quality of the cut and can affect the performance of a diamond. A diamond with facets cut only a few degrees out of alignment can result in a poorly performing stone. For a round brilliant cut, there is a balance between "brilliance" and "fire". When a diamond is cut for too much "fire",