Quartz Stone: How Is It Processed and What Is It Good for?
Quartz, also known as silica, is one of the main rock-forming minerals with very stable physical properties. It is mainly used to produce quartz sand (also known as silica sand).
Quartz and quartz sand (silica sand)
Physical properties of quartz
| Chemical formula | SiO2 |
| Color | Colorless and transparent |
| Luster | Vitreous luster |
| Mohs hardness | 7 |
| Fracture | Conchoidal with greasy luster |
| Density | 2.65 g/cm3 |
| Melting point | 1750 ℃ |
| Crystal Structure | Hexagonal |
What are the quartz raw ores?
At present, vein quartz is the main source of producing quartz sand. The proportion of quartz sandstone and cobblestone is not high.
The main source of producing quartz sand
- 1 Vein quartz
- 2 Quartz sandstone (tailings in kaolin, etc.)
- 3 Weathered (powdered) quartz
- 4 Other siliceous materials (pebbles, etc.)
What are the basic requirements for quartz sand?
Quartz sand made by quartz rocks
- 1 The color of quartz sand should be consistent. There should be no second color in it.
- 2 The particle size composition should be uniform. There should not be too many coarse or fine particles.
- 3 The product has good cleanliness and no dust.
- 4 Its moisture content should be less than 0.5%.
How do you crush quartz stone (produce quartz sand)?
Quartz sand production process is divided into raw quartz ore — quartz crushing — quartz sand making — sand washing — drying — magnetic separation — finished products.
Quartz ore crushing
A jaw crusher is selected for crushing quartz stone to a particle size of about 150 mm. The advantages of the jaw crusher are large throughput and feeding size, simple and convenient maintenance, and low cost.
Quartz stone is a material with higher hardness, so the cone crusher is the best choice in the second-stage crushing.
Although an impact crusher can also be used in the second-stage crushing, it is more suitable for processing brittle materials.
Therefore, in the crushing process of quartz stone, it is better to choose a cone crusher as the secondary crushing equipment.
Quartz sand making
If you need to process quartz stone for sand, you need to choose the corresponding sand making machine.
VSI sand making machines are commonly used. The VSI sand making machine adopts "rock on rock" and "rock on iron" to make sand.
It not only has high crushing efficiency, but also saves energy by using the inertia of the quartz stone itself.
Mobile crushers have been widely used in the field of quartz stone crushing. The mobile crusher can realize the transition function at any time for in-site processing.
It can adapt to the harsh and complex working environment, saving time and effort, and realize the remote control of multiple operations by integrating the PLC intelligent control system.
If the site is complex and inconvenient to install a fixed production line and the quartz stone raw material is not suitable for transportation, a mobile crusher can be selected.
Washing and drying
The quartz sand crushed to 0-5 mm by the sand making machine can be sent to the sand washing machine for washing. The soil is removed from the sand and the wastewater can be recycled.
Finally, the quartz stone is sent to the dryer for drying. The evaporation strength is 80-100 when drying quartz sand, and the final moisture can reach 0.5-1% or less.
How is artificial quartz stone manufactured?
Usually, the quartz stone we say is a new type of stone artificially synthesized by more than 90% of quartz crystals plus resin and other trace elements.
First, stir the materials (including resin and quartz sand, etc.) in a special mixer. Then spread the materials into the mold and send them to the press for molding. Next, send the plates to the curing furnace for curing, and the final step is the subsequent processing (including polishing, cutting, etc.).
| Materials | Proportion |
| Quartz sand (5-100 mesh) | 60-63% |
| Quartz powder (320-2500 mesh) | 28-32% |
| Unsaturated polyester resin (UPR) | 7-9% |
| Coloring material and couplint agent | 0.4-0.6% |
| UV absorber | 0.5-1% (amount of resin) |
| Decomposition agent | 0.5-1% (amount of resin) |
| Curing agent | 0.5-1% (amount of resin) |
The ratio of quartz sand and quartz powder is about 88-95%. Therefore, when producing artificial quartz stone, quartz sand and quartz powder are indispensable.
What are the characteristics of quartz stone?
Abrasion resistance
Quartz stone has high hardness, second only to diamond, so it is highly scratch-resistant and wear-resistant.
Heat resistance
Unlike artificial stone made of acrylic resin, it will not be deformed due to contact with slightly high-temperature objects (such as hot water, oil, appliances, etc.) or due to natural temperature differences. Its high-temperature resistance can reach 200-250 degrees.
The characteristics of quartz stone
Anti-pollution
The surface and the inside of the quartz stone are both dense and uniform, which can prevent the growth of bacteria and is good for food hygiene and human health.
Non-color fading
Quartz stone does not fade or change color. In the process of long-term daily life indoor use, it will not be faded, toned and tarnished due to oxidation, aging, corrosion, and contact with hot objects.
Quartz vs granite vs marble (price included)
What is the difference between quartz, granite and marble? Which is more expensive? See the table below:
| Features | Quartz | Granite | Marble |
| Scratch resistance | ● | ● | |
| Pollution resistance | ● | ● | |
| Antibacterial property | ● | ||
| Heat resistance | ● | ● | ● |
| Pressure resistance | ● | ● | |
| Uvioresistant | ● | ||
| Glossiness | ● | ● | |
| Mohs hardness | 7 | 6 | 4 |
| Price/per square foot | $50 - $120 | $35 - $75 | $40 - $100 |
What is the quartz stone good for?
Quartz is widely used in glass, casting, ceramics, rubber and plastics, machinery, construction and building materials industries.
Glass
Quartz glass has been widely used due to its low thermal expansion coefficient, good thermal shock stability, electrical properties and chemical resistance.
Ceramics
Quartz can not only shorten the drying time and prevent the deformation of the ceramic body, but also increase the binding ability, mechanical strength and transparency of ceramic body, making the glaze transparent and bright.
Rubber and plastics
Due to its excellent properties such as non-toxic, odorless, non-polluting, good temperature resistance, acid and alkali corrosion resistance, quartz powder is widely used in silicone rubber such as silicone rubber gloves, sealing rings, shoe materials, etc.
Mechanical
The market share of quartz sand products in the foundry industry is about 40%. It is used to prepare molding sand and core sand in the production of foundry sand.
Building
Quartz stone can also be used as construction aggregate after being crushed, and can be used in concrete, cementitious materials, road construction materials, artificial marble, cement physical performance inspection materials (i.e. cement standard sand) and other fields.
Building materials industry
Quartz stone countertops with various colors can be widely used in public buildings and home decoration fields.
It is an environmentally friendly and reusable interior decoration material without any radioactive.
