Quartz Mining

What is Quartz

Quartz is one of the most common minerals in the Earth’s crust. As a mineral name, quartz refers to a specific chemical compound (silicon dioxide, or silica, SiO2), having a specific crystalline form (hexagonal). It is found is all forms of rock: igneous, metamorphic and sedimentary. Quartz is physically and chemically resistant to weathering. When quartz-bearing rocks become weathered and eroded, the grains of resistant quartz are concentrated in the soil, in rivers, and on beaches. The white sands typically found in river beds and on beaches are usually composed mainly of quartz, with some white or pink feldspar as well.

Quartz Mining

Quartz crystal is found in many countries and many geologic environments. Major producers of natural quartz crystals are the United States (particularly Arkansas) and Brazil. Natural quartz is rarely used as found in nature (especially in electrical applications), except as a gemstone. Natural quartz crystals have too many chemical impurities and physical flaws. As a result, a commercial process of manufacturing pure, flawless, electronics-grade quartz was developed. “Cultured quartz,” that is, quartz crystals grown very carefully in highly controlled laboratory conditions, is the quartz that is used in industry. About 200 metric tons of cultured quartz is produced each year. In the production of cultured quartz crystals, a “seed crystal” is needed. A seed crystal is a small piece of carefully selected, non-electronics-grade quartz. The manufactured crystal grows on this seed crystal.

Quartz Uses

Quartz crystal is one of several minerals which are piezoelectric, meaning that when pressure is applied to quartz, a positive electrical charge is created at one end of the crystal and a negative electrical charge is created at the other. These properties make quartz valuable in electronics applications. Electronics-grade manufactured quartz is used in a large number of circuits for consumer electronics products such as computers, cell phones, televisions, radios, electronic games, etc. It is also used to make frequency control devices and electronic filters that remove defined electromagnetic frequencies.

Quartz Mining Process

Washing and classifying desliming
The SiO2 grade in Quartz Sand（Silica Sand） decreases by Quartz Sand（Silica Sand） size becoming finer, so washing and desliming of crude Quartz Sand（Silica Sand） is necessary before next step.

Scrubbing
Scrubbing is the way to remove film iron and impurity minerals on the surface of quartz by mechanical force and crush these mineral aggregate. The Quartz Sand（Silica Sand） gets further purification by classification. There are two kinds of methods rob scrubbing and mechanical scrubbing. Flotation
The separation of mica and quartz is difficult, the effective methods: anionic collector in acid condition and anionic - cationic collector in alkaline condition. The purification of Quartz Sand（Silica Sand） can reach 99% after scrubbing, desliming, magnetic separation and flotation. Acid Leaching
Dilute acid had a significant effect on removing iron and aluminum, and concentrated acid for the removal of titanium and chromium, and mixed acid for mineral impurity. Control various factors of acid leaching should be based on quartz final grade requirements, and as far as possible reduce the acid concentration, temperature and dosage to achieve quartz purification.

Cases Study - Quartz Mining

5TPH Quartz Rock Gold Mining Process in Nigeria

Material: Hard rock gold deposit
Capacity: 5TPH
Country: Nigeria
Feeding size: 0.6-1.3mm
Raw mineral description:
1. Mineral type: rock gold deposit, gold in quartz rock
2. Mineral composition: Au. 43%; Ag. 19%; Fe. 3%; Zn. 5.6%. Customers requirements:
increase the gold grade as much as possible.