会社のニュース The application process of UV LED lamp in mineral identification

The core of the application of UV LED lamps in mineral identification is to use ultraviolet light to stimulate the fluorescent substances within the mineral, causing them to emit visible light of different colors, thereby revealing their unique "identity." This process is generally divided into three main steps: excitation, observation and analysis, and application scenario.

The fluorescence phenomenon of minerals is a process in which specific elements (usually impurities or activators) inside the mineral release energy in the form of visible light after absorbing ultraviolet light. Different minerals and activators require different wavelengths of ultraviolet light to be effectively excited. Therefore, choosing the right UV LED lamp is the first step.

• Long-wave ultraviolet (UVA): With a wavelength between 315nm and 400nm, it is the most commonly used light source for mineral fluorescence excitation. Most fluorescent minerals, such as fluorite, calcite, and scheelite, fluoresce brightly under long-wave UVA. UVA LEDs are relatively safe and can be used directly in the field or in the laboratory.
• Short-wave ultraviolet (UVC): With a wavelength between 100nm and 280nm, it has higher energy. Some minerals that do not fluoresce under long-wave UVA, such as certain silicates and opals, can emit a distinctive fluorescence under short-wave UVA. Short-wave UVA is harmful to the human body, so professional eye protection and other protective equipment must be worn when using it.

When a mineral fluoresces under UV LED light, observers carefully note its characteristics, including:

• Fluorescence color: This is the most intuitive characteristic. For example, fluorite typically glows bluish-purple under UV light, while calcite may glow red, orange, or yellow. Scheelite, for example, emits a distinctive bright blue. The fluorescence color can provide a preliminary indication of the mineral's type.
• Fluorescence intensity: Some minerals fluoresce very brightly, while others fluoresce only faintly. Fluorescence intensity can provide clues to the mineral's purity and crystal structure.
• Phosphorescence: Some minerals continue to glow for a period of time after the UV light is removed. This phenomenon is called phosphorescence. Observing the duration of phosphorescence (ranging from seconds to minutes) can also aid in mineral identification. For example, some rhodochrosites glow red under UV light, and this red glow persists for several seconds after the light source is removed.

UV LED lamps are not limited to the laboratory; their portability makes field exploration more efficient.

• Field Exploration: At night or in dimly lit mines, geologists use UV LED lamps to illuminate rock walls and search for fluorescent minerals. This method is faster and more efficient than traditional visual inspection or chemical testing, enabling the rapid location of important mineral resources such as uranium and tungsten.
• Gem Identification: Gemologists use UV LED lamps to verify the authenticity and origin of gemstones. For example, natural and synthetic diamonds typically fluoresce differently under UV light; and the color and intensity of the fluorescence emitted by certain rubies under UV light can help determine their origin.
• Museums and Collections: Museum curators also use UV LED lamps to examine mineral or gemstone specimens to identify dyes, fillers, or restorations, ensuring the authenticity and integrity of their collections.

In summary, UV LED lamps convert fluorescence phenomena that are invisible to the naked eye into intuitive visual information by providing a stable and controllable ultraviolet light source, greatly improving the efficiency and accuracy of mineral and gem identification.