How to cultured quatrtz

“cultivated quartz” or “cultured quartz”, that is, quartz materials made in a laboratory or factory environment using specific techniques and methods by artificially simulating the conditions under which natural quartz (crystal) is formed.

Cultivation methods and principles

• （Hydrothermal Method）：
  • Principle: This is one of the most commonly used methods for cultivating artificially cultivated quartz. High-purity natural quartz raw materials (such as quartz sand, etc.) are placed in a special autoclave as a solute, and mineralizing agents (common alkaline substances such as sodium hydroxide and sodium carbonate) are added at the same time, and then the autoclave is sealed and a high-temperature and high-pressure aqueous solution is injected into it. In the environment of high temperature (generally around 300°C – 600°C) and high pressure (about 1000 – 1500 atmospheres), the quartz raw material will be dissolved into an aqueous solution under the action of a mineralizer to form a supersaturated solution. After that, the seed crystal (usually a natural crystal with good quality or a previously cultivated quartz crystal is selected as the seed crystal) is used to guide the crystallization, and the silicon atoms in the solution will be deposited and grown on the surface of the seed crystal in an orderly manner according to a certain lattice structure, and finally form a large-size and high-quality artificially cultivated quartz crystal.
  • For example, in industrial production, quartz crystals cultivated by hydrothermal method have high transparency and relatively uniform internal structure, which can be used to manufacture high-precision quartz crystal oscillators and other electronic components to meet the needs of electronic products for stable clock signals.
• （Flux Method）：
  • Principle: Quartz raw materials are mixed with a specific flux and then heated and melted, this flux can lower the melting point of quartz, making it easier to enter the liquid state. Then, by means of slow cooling, quartz crystals are precipitated and grown from the melt. The flux plays a role in regulating the growth environment and promoting the nucleation and growth of the crystal, but different flux formulations will have an impact on the characteristics of the final quartz crystal.
  • For example, when exploring new quartz crystal materials, researchers sometimes use the flux method, and try to cultivate quartz crystals with special physical and chemical properties (such as special optical properties, electrical properties, etc.) by adjusting the flux composition and growth conditions, which are used in some specific experimental research or high-tech fields.

Nurturing environment and equipment

• Environmental conditions:
  • Temperature control: Whether it is a hydrothermal or flux method, precise temperature control is required. In the hydrothermal method, the temperature deviation may affect the dissolution rate of quartz raw materials, the saturation of the solution and the crystal growth rate, etc., and then affect the crystal quality. In flux methods, temperature changes are also critical to the process of crystal precipitation and growth from the melt, so a high-precision temperature control system is generally used to ensure that the temperature is stable within a set range, and the error is usually controlled within a small range (e.g., ± a few degrees Celsius).
  • Pressure control (for hydrothermal processes): The high-pressure environment in hydrothermal processes requires specialized pressure maintenance and regulation devices, as the right pressure is one of the key factors to ensure that the quartz raw material can be fully dissolved and the crystals can grow properly. Excessive or low pressure can lead to defects in the crystal, such as cracks, uneven growth, etc., so it is important to stabilize the pressure at an appropriate value, such as 1000 – 1500 atmospheres.
  • Cleanliness requirements: The cultivation environment needs to maintain a high degree of cleanliness to avoid impurities from mixing into the growing quartz crystals and affecting their quality. For example, in the cultivation process of high-precision quartz crystals used in the electronics industry, even the smallest impurity particles may change the electrical properties of the crystals, so the entire cultivation process is usually carried out in a clean room or an environment with strict dustproof and anti-pollution measures.
• Equipment:
  • Autoclave (key equipment for hydrothermal method): This is the core equipment for hydrothermal cultivation of quartz crystals, its material needs to be able to withstand high temperature and high pressure environment, the internal structure should be convenient for placing raw materials, mineralizers and seed crystals, etc., and should have good sealing to prevent solution leakage and pressure runaway. At the same time, it is also equipped with heating devices, temperature sensors, pressure sensors and corresponding control systems to achieve precise control of temperature and pressure.
  • Furnace (common equipment for flux method): used to heat the mixture of molten quartz raw material and flux, it needs to have adjustable heating power and uniform heating function to ensure the uniform quality of the melt and facilitate the subsequent crystal growth. Temperature monitoring and control devices are also connected to ensure that the required temperature is met throughout the melting and cooling growth process.

peculiarity

• Strong quality controllability: Compared with natural quartz, artificially cultivated quartz can make the grown crystals have higher consistency and stability in terms of purity, size, crystal structure integrity, and physical and chemical properties by precisely regulating the cultivation conditions (such as temperature, pressure, raw material purity, seed crystal quality, etc.). For example, in the manufacture of quartz materials for optical lenses, through strict control of cultivation parameters, it can ensure that each batch of quartz crystals has similar refractive index, transparency and other optical properties, and meet the high-precision requirements of optical instruments for lens materials.
• Special requirements can be met: quartz crystals with specific properties can be cultivated according to the needs of different application areas. For example, in the field of laser technology, quartz crystals are required to have specific optical uniformity, laser transmittance and thermal stability, etc., and artificially cultivated quartz that meets these requirements can be manufactured by adjusting the cultivation methods and parameters, providing key material support for the manufacture of laser equipment.
• Cost-effective advantage: In the case of large-scale industrial production, artificially cultivated quartz can effectively reduce production costs. On the one hand, there is no need to involve complex mining, screening and other costly and resource-limited links like the mining of natural quartz; On the other hand, by optimizing the cultivation process and improving the production efficiency, the supply of quartz materials that meet the standards can be stably supplied to meet the growing demand for quartz crystals in the market, especially in industries with large quantities of quartz crystals such as the electronics industry, which can bring significant cost savings.

Contrast with natural quartz

• Internal structure and features:
  • Inclusions differences: In the long geological formation process, natural quartz will inevitably contain a variety of natural inclusions, such as gas-liquid inclusions (tiny cavities containing gas and liquid), mineral inclusions (such as rutile, tourmaline and other mineral crystals are wrapped in quartz), etc., these inclusions have different shapes and irregular distribution, which is one of the important identification characteristics of natural quartz; Artificially cultivated quartz, on the other hand, is grown in a relatively pure and controlled environment, and there are usually few internal inclusions, and even if there are some regular residues of additives or artificially introduced marker features that may be related to the cultivation process (such as inclusions formed by specific substances specially added in some special cultivated quartz for scientific research to facilitate the tracking of the growth process).
  • Difference in growth texture: The growth texture of natural quartz often shows natural continuity and irregularity, and may have texture characteristics such as bending and twisting that conform to the natural growth law; The growth texture of artificially cultivated quartz sometimes shows relatively regular and regular characteristics, such as the growth texture of quartz crystals cultivated by hydrothermal method, which may extend more neatly along the direction of the seed crystal, and the differences in these textures can be found through microscope and other observation methods.
• In terms of physical and chemical properties:
  • Overall similarity: Both cultivated quartz and natural quartz are mainly composed of silicon dioxide (SiO₂), so the basic physical and chemical properties (such as hardness, density, chemical stability, etc.) are similar. For example, they all have a hardness of about 7 on the Mohs scale, have good chemical stability in general acid-base environments, and have densities in the range of about 2.65 grams per cubic centimeter.
  • Subtle differences: However, there are subtle differences that can be found in some high-precision measurements or specific performance requirements. For example, in terms of optical properties, although the refractive index and other indicators are similar, in terms of optical uniformity, artificially cultivated quartz can achieve a higher degree of uniformity than natural quartz if the cultivation conditions are well controlled, which makes it more advantageous in fields with strict requirements for optical performance such as optical instruments; In terms of electrical performance, for quartz crystals used in electronic components, artificially cultivated quartz can make its electrical properties (such as piezoelectric effect) more stable and in line with design standards through more precise doping and other processes, which is better than the uneven performance of natural quartz in this regard.

Fields of application

• Electronics industry: Artificially cultivated quartz is widely used in the manufacture of quartz crystal oscillators, filters, sensors and other electronic components due to its stable and precisely regulated physical and chemical properties, especially the excellent piezoelectric effect (the characteristic of generating electric charge when subjected to pressure), and is one of the key materials for modern electronic products (such as mobile phones, computers, communication equipment, etc.) to operate stably and achieve accurate signal processing. For example, the clock module in a mobile phone relies on a quartz crystal oscillator to provide a stable clock signal to coordinate the work of various components.
• Optical instruments: Its good optical properties, including high transparency, suitable refractive index, low dispersion and achievable optical uniformity, make artificially cultivated quartz have important applications in the manufacture of optical lenses, prisms, lenses and other optical components. For example, in high-precision optical instruments such as microscopes, telescopes, and laser equipment, the optical components made of artificially cultivated quartz can ensure the accurate refraction and reflection of light and high-quality imaging effects, and improve the overall performance of the instrument.
• Scientific research field: It provides ideal research materials for scientific researchers, who can customize quartz crystals with specific properties (such as special electrical, magnetic, optical properties, etc.) according to experimental needs, and use them to explore new physical phenomena and develop new materials and technologies. For example, in the research of superconducting materials, quantum physics and other cutting-edge scientific research fields, special samples made of artificially cultivated quartz can help researchers conduct experimental observation and data analysis more accurately, and promote the continuous development of scientific research.

In short, artificially cultivated quartz plays an indispensable role in many important fields, and with the continuous progress of technology, its cultivation methods are more perfect, and the application prospects are more and more broad.