#4 - Growing Crystals

Research on crystals and their structures is a field called crystallography. A crystal is a molecule composed of various atoms and arranged in a uniform repeating pattern based on its unique shape. This results in materials with specific shapes and colors and other properties. Crystals can be big or small, but they all have the same "shape". Please look at the crystal display of the laboratory. Salt and sugar are examples of crystals. The salt is NaCl and is in the form of a cube. Snow crystal has a hexahedral structure. Diamonds (for jewelry tools and cutting tools) are also examples of quartz, made of pure carbon. Graphite (for pencils and lubricants) is also made of carbon.

In solution, solvent (water) can hold only a certain amount of solute. This is called solution solubility. As the temperature of the solution rises, hot water can dissolve more solids than cold water. This is because the heated water molecules move farther and have room to dissolve more solids. The solution is said to be saturated when it is no longer able to dissolve the solid material. When this solution cools, the water molecules gather again and the solution retains as much space as possible to dissolve the solids.

When water is released from excess solute, crystals are formed and accumulation begins. This process is called recrystallization, depending on the condition a lot of small crystals and one large crystal quality is obtained.

In this experiment, crystals are grown from a saturated solution. During recrystallization, crystals begin to grow through a process called "nucleation". Dust particles on the surface of the solution may initiate crystallization. However, this situation is somewhat uncontrolled. In order to achieve controlled growth, "seeds" are tied in a line and immersed in solution. As the temperature of the solution continues to drop, more crystals will accumulate in the yarn. The rate at which crystallization occurs affects the quality of the crystal. The best crystals grow slowly.

In nature, perfect crystals rarely see the surface formed on the crystal depending on the space available for crystal growth. If crystals grow together or grow in a restricted environment, a shaped crystal surface may not be formed. However, symmetry may not be readily apparent from these general forms, but crystals sometimes form several forms that are more general than other crystals. The term used to describe the general shape of a crystal is a habit. Crystals usually contain atomic planes and bonds between atoms are weaker than others. In this case, if minerals strike hard objects, they tend to rupture along these faces. This property breaking along a certain plane is known as cleavage. Since cleavage occurs along a plane within the crystal lattice, it can be described in the same way as the crystalline form is described.

A crystal is a collection of atoms or molecules built up in a specific repeatable pattern. The pattern can be simple or complex. New crystals are most likely to grow by adhering to the front crystal surface. Newly growing quartz often does not fit perfectly with existing crystals. Therefore, new crystals grow with so-called "placement mistakes". This is one of the reasons why small crystal clusters are common, but large perfect crystals are rare. Many other environmental factors will determine the completeness of the crystal

In this experiment, crystals are grown from a saturated solution. During recrystallization, crystals begin to grow through a process called "nucleation". Dust particles on the surface of the solution may initiate crystallization. However, this situation is somewhat uncontrolled. In order to achieve controlled growth, "seeds" are tied in a line and immersed in solution. As the temperature of the solution continues to drop, more crystals will accumulate in the yarn. The rate at which crystallization occurs affects the quality of the crystal. The best crystals grow slowly.