Okay Miley, we know you're not Hannah Montana anymore, but becoming a woman does not mean throwing away your bra! The actress certainly decided that less was more when it came to her blazer style dress at 2012 Billboard Music Awards, but we have to disagree; her bouffant hair-do was definitely the only thing right about this look (though now she's got rid of that too!). It seems to be common amongst child stars to attempt to establish their womanhood by showing off their assets by verging on public indecency; however, we think in this case, Miley's sophistication is at an all-time low. In ancient civilizations, such as Greece and Rome, small and symmetrical breasts were favored, reflecting a preference for modesty and balance. During the Renaissance, full breasts with a gentle slope were idealized, representing fertility and motherhood. In the 20th century, the advent of Hollywood glamour led to a shift towards more voluptuous figures, exemplified by icons like Marilyn Monroe. Euhedral fluorite crystals are typically cubes, but sometimes they are octahedra like those shown in Figure 3.69 below. Fluorite is the most common example of a mineral that has four perfect cleavages; the cleavage directions are parallel to the octahedral faces. Many fluorite cleavage fragments are perfect octahedra, and many cubic fluorite crystals are missing corners because of the mineral’s cleavage. All fluorite is essentially CaF 2 but color varies due to minor chemical impurities. Purple is the most common color, but the other hues in this figure are quite common too. 3.69 Fluorite The term parting refers to breakage of minerals along directions of structural weakness, such as twinning. Gemstone cleavage is usually described with reference to crystallographic axes and directions and is also graded according to its "perfection," or ease with which the gem can be spilt along the cleavage.

From the flatter chests of the 1920s to the overwhelming embrace of full cleavage today, these are the best boobs that have been considered ideal in the last century. Whether it’s a cleavage making “upper breast fullness,” perkiness, or an athletic look, what we consider to be the “best boobs” continues to evolve. While we know taste is subjective, this list of celebrity women with the best breasts have made an impression on the world at large. Best applied each morning for tighter, brighter and more nourished skin, to support an area that's often neglected and prone to damage. Gems with perfect cleavage are easiest to split, while those with no cleavage are hardest to split. Variable Cleavage Within a Single Crystal Just as wood is easier to split with the grain than against it, gemstone cleavage is the tendency of certain crystals to break along definite plane surfaces. If there are planes in a crystal structure with relatively weak atomic bonds, the crystal is more likely to break along those planes. Green fluorite with prominent cleavage. Photo by Eurico Zimbres and Tom Epaminondas. Licensed under CC By-SA 2.0 BR.The term cleavage in gemology only applies to crystalline materials. For example, since glass is a super-cooled liquid in which the atoms are not arranged in a long-range periodic array, it can have no cleavage because there are no uniform bond layers. Of course, glass can break. However, since it has no crystalline structure, it doesn't have internal cleavage planes. Glass has an amorphous atomic structure. "The Shape of Broken Glass (2)," photo by zeevveez. Licensed under CC By 2.0. Cleavage Grades

Not even the over-elaborate patterned dress was enough to distract from 'The Notebook' star's mega side-boob moment on the red carpet at the UK premiere of 'Morning Glory' in 2011. Don't be fooled by the innocent dimples and dazzling smile; this girl is not afraid to flash the flesh. However, we think she suits the look with her slender frame and she definitely deserves some credit for managing not to have an embarrassing slip the whole night. And, having had red carpet wardrobe malfunctions in the past, we can't help but applaud her bravery. C leavage, fracture, and parting are three related terms that describe how a mineral crystal may break. The orientation and manner of breaking provide important clues about crystal structure and can be keys to mineral identification. If breaking produces planar and smooth surfaces, oriented in a particular way relative to a crystal’s atomic arrangement, we say that the mineral has cleavage. Diamond and graphite provide examples of cleavage. Each is composed solely of a single element, carbon. In diamond, each carbon atom is bonded to four others in a tetrahedral pattern with short covalent bonds. The planes of weakness (cleavage planes) in a diamond are in four directions, following the faces of the octahedron. In graphite, carbon atoms are contained in layers in a hexagonal pattern where the covalent bonds are shorter (and thus even stronger) than those of diamond. However, each layer is connected to the other with a longer and much weaker van der Waals bond. This gives graphite a single direction of cleavage, parallel to the basal pinacoid. So weak is this bond that it is broken with little force, giving graphite a slippery feel as layers shear apart. As a result, graphite makes an excellent dry lubricant. [2] The vast majority of minerals exhibit cleavage, but the nature of cleavage is highly variable, and some minerals cleave much more easily than others. We use general terms to describe the quality of a cleavage, including: perfect, imperfect, distinct, good, fair, and poor. Although some minerals exhibit no cleavage, many cleave in more than one direction, but the qualities of the different cleavages may not be the same. Dodecahedral cleavage occurs when there are six cleavage planes in a crystal. Sphalerite has dodecahedral cleavage.Under ideal circumstances, a cleavage plane might be virtually smooth and flat on an atomic scale. A break in a gemstone that doesn't occur along cleavage planes is either a fracture or a parting. Gemstone Cleavage