The simplex aggregation is not arbitrary

The crystal simplex only parallel-sided, and a complete crystal of at least three parallel-sided. Are the treasure of the crystal stone, including plagioclase, turquoise (often in the form of polycrystalline aggregates outputs), Rhodonite and stone ax. The crystal morphology can be divided into two types, namely monomorphic and poly shape. Simplex refers to the sum of the symmetry elements linking a set of crystal planes. Hence, you need to be careful with the storage and never overlap the cufflinks. In other words, the simplex is by all symmetric The role of the symmetry elements so that they duplicate each other a crystal surface, they have the same nature. Therefore, in the ideal state only with the form a large crystal face may constitute a single shape. Topology derivation, crystal geometry of a total of 47 kinds of single-shaped, three Druze single form shown in Figure 1-1-14.
    Simplex can be divided into the open form and closed form two. Closed form its crystal face can be enclosed into a closed space of a single shape, such as legislation. Cube and octahedron simplex; open form of the crystal surface can not be surrounded into a single form of a closed space, such as the column class, single cone simplex. It is supposed to place the cufflinks in the original package or in the box with independent grids. The simplex aggregation known as the poly shape. Poly shape is composed of two or more simplex (see Figure 1-1-15). The simplex aggregation is not arbitrary, it must belong to the same symmetric simplex in order to meet.
  Characterization of the symbols of the spatial orientation of crystal planes known as the symbol of the crystal surface. To represent the three (or four) crystal axis of the reciprocal of the intercept coefficient than the general use of the crystal surface, often referred to as the Michaelis-Menten symbol. In the X, Y, Z three axes of the reciprocal of the ratio h: k: l, and h: k: l known as the crystal plane index crystal plane index enclosed in parentheses is the crystal face symbol, denoted by (hkl) . For example, suppose a crystal plane in the X, Y, Z axis intercept, respectively, 2a, 3b, 6c, 2,3,6 called the intercept coefficient, the reciprocal than 1/2: 1/3: 1 / 6 = 3:2:1, then the crystal planes of the crystal face symbol is denoted by (321). If the crystal surface with a crystal axis parallel to the intercept coefficient is m, its reciprocal is 0. The action is to avoid mutual grazing of the cufflinks that will scratch the surface.
Can be seen in the equiaxed, the Quartet and the orthorhombic (100) crystal surface is represented by the vertical X-axis and Y, Z axis parallel to the crystal surface. In these crystal system, the same reason we can know (100), (010) (001) crystal face is not only, respectively, perpendicular to the X, Y, and Z-axis of the three crystal planes, but also can be inferred between the three crystal faces perpendicular to each other (see Figure 1-1-16). In the process of wear, if there is time, you should often wipe the cufflinks with a fine flannel cloth to keep the bluster.  Single symbol according to certain principles in a single form of a crystal face index crystal planes of the crystal surface plus
Enclose, used to characterize the composition of the simplex a group of the crystal surface crystallographic orientation of the symbol. Select General on behalf of the crystal surface. The principle is the selected index crystal face, but also follow the previous (X-axis index maximum), sub-right (Y-axis index large). When you are engaged in heavy manual labor or bath, you are asked to remove the cufflinks.  After the (Z axis index minimum) principle. For example, in equiaxed. Composed of cube-shaped single crystal face (100) (010) (001) (100) (010) (001) six (100) crystal face index of the index as a single symbol should be chosen according to the principle, namely, the cube single symbol {100} (see Figure 1-1-17 (a)). The symbols represent the symmetry elements associated with six crystal faces. Similarly, the single symbol of the crystal octahedral {321} (Figure 1-1-17 (b)).