"Faden Quartz" also called Faden Rock crystal from Afghanistan.

Faded Quartz are tabular Quartz crystals that have a thread-like line running through them, perpendicular to the line of growth. Faden Quartz is said to be excellent for transmitting energy, and is believed to contain a lot of information related to our Earth.

Quartz is a form of silicon dioxide, SiO2 and is one of the most abundant minerals on the earth's crust. It represents more than 12% of the volume of the earth's crust (including granite, sand). Quartz has two modifications: α-quartz is trigonal, β-quartz (a higher temperature form) is hexagonal. In addition, silicon dioxide occurs in many other structures such as α- and β-cristobalite, keatite, tridymite, coesite, stishovite, melangophlogite and lechatelierite. Although quartz consists of silicon dioxide, it is often classified as a tectosilicates. The reason for this is that quartz forms a network of SiO4 tetrahedra. Each oxygen atom is shared by two silicon atoms. Individual SiO2 molecules only occur with gaseous silica. Quartz can be very pure, like rock crystal, but it often contains impurities. These impurities can consist of ions that are incorporated into the crystal lattice during the growth of the crystal. Quartz crystals can contain between 13 and 15,000 ppm Al3 +, between 9 and 1400 ppm Na +, between 3 and 300 ppm K + and traces of Fe3 +, Ti4 +, P5 +, H + and Li +. The aluminum and iron, in combination with ionizing radiation, are responsible for the color of a number of quartz varieties. Furthermore, quartz crystals can grow over other minerals, as is the case with rutile quartz. Quartz can form large crystals as well as form microscopic aggregates. The largest quartz crystals are found in Farm Verloren in Namibia. Quartz crystals up to 20 meters, and possibly 50 meters, and dolomite crystals up to 2 meters are found here. When quartz is melted, it often forms a glass on rapid cooling, because the crystallization process takes quite a lot of time. Quartz is a piezoelectric material and the vibrations that can be generated in the lattice of the crystal are used in electronic equipment such as quartz clocks and radios. Quartz is formed, among other things, by crystallization during the cooling of a molten silicate mass. It is therefore an important rock-forming mineral in felsic igneous rocks, such as granite. However, the largest crystals are formed by the influence of hot water on rocks. Quartz dissolves in the surrounding rock in the form of orthosilicic acid and precipitates in cavities and cracks when the solution cools. Quartz can also crystallize in geodes due to the leaching of the surrounding rock. Quartz is chemically inert and does not dissolve well in water under atmospheric conditions. The water solubility is between 6 and 11 mg / l at 25 ° C. This means that quartz hardly dissolves when quartz-containing rocks are weathered. Because of this, the most common form of quartz is sand and sandstone.