A break in the acetabulumâthe socket located on each side of the pelvisâis less common than other types of pelvic or hip fractures. It usually occurs as the result of a car accident or fall from a significant height, with damage to other bones and soft structures in and around the hip and pelvis.
Diamonds are nevertheless classified as minerals, because they adhere to the five core characteristics of minerals. In addition to being formed by a natural process, minerals are stable at room temperature. This simply means that all minerals are solid at normal temperatures and pressures common on the Earthâs surface. This characteristic excludes water from being a mineral because of its liquid state but includes the solid form of water â ice â as a valid mineral. Minerals are also represented by a chemical composition or atomic structure. Minerals all share a uniquely orderly internal order.
A mineral's hardness is not necessarily constant for all sides, which is a function of its structure; crystallographic weakness renders some directions softer than others. An example of this property exists in kyanite, which has a Mohs hardness of 5Â½ parallel to [001] but 7 parallel to [100].or example, quartz is defined by its formula, SiO 2, and a specific crystalline structure that distinguishes it from other minerals with the same chemical formula (termed polymorphs). When there exists a range of composition between two minerals species, a mineral series is defined.