Fluorescence Minerals
Fluorescent minerals also display this property. They absorb ultraviolet light at specific wavelengths (shortwave: 253.7 nm; longwave: 350 nm and 368 nm) and then emit fluorescent colored light. The fluorescence color of minerals is highly diverse: orange, green, red, blue, yellow, white, pink, purple, and various shades in between. This diversity of colors depends on different factors:
- In some minerals, it is related to the intrinsic properties of the mineral itself (these minerals always fluoresce in a specific color).
- In others, it is determined by the fluorescence activator present within the mineral (these minerals can appear in multiple colors).
Sometimes, a geological specimen is a combination of several minerals, each exhibiting its own fluorescence. Such samples are exceptionally beautiful. There are also rare specimens that appear in one color under a certain wavelength but in a completely different color under another wavelength—these are particularly fascinating and unique.
Some of the most common fluorescent minerals found worldwide include: calcite, fluorite, aragonite, cerussite, anglesite, scheelite, hydrozincite, halite (salt), apatite, barite, and gypsum. On the other hand, some fluorescent minerals are extremely rare and occur only in specific regions of the world, such as certain minerals from Greenland.
The Earth Science Park Museum in Mashhad, by equipping itself in 2017 (1396 in the Iranian calendar) with special ultraviolet lamps for displaying fluorescent minerals, managed to identify a significant number of fluorescent minerals from various regions of Iran. These specimens, along with samples from other parts of the world, are exhibited in a dedicated Fluorescent Minerals Room.
