4.9" Fluorite & Galena Cluster - Rogerley Mine

Here is a nice 4.9" cluster of Rogerley fluorite and galena from the famed Rogerley Mine in County Durham, England. The plate has beautiful, pristine green cubic fluorite crystals, with some crystals up to .5". There are also a many tiny galena crystals peppered throughout the matrix. This particular kind of fluorite is unique in that it will actually fluoresce a beautiful purple-blue color in natural light alone! Under long and short wave UV lighting, this specimen fluoresces a vibrant purple.

Fluorite is a halide mineral comprised of calcium and fluorine, CaF2. The word fluorite is from the Latin fluo-, which means "to flow". In 1852 fluorite gave its name to the phenomenon known as fluorescence, or the property of fluorite to glow a different color depending upon the bandwidth of the ultraviolet light it is exposed to. Fluorite occurs commonly in cubic, octahedral, and dodecahedral crystals in many different colors. These colors range from colorless and completely transparent to yellow, green, blue, purple, pink, or black. Purples and greens tend to be the most common colors seen, and colorless, pink, and black are the rarest.

Galena is the natural mineral form of lead sulfide. It is the most important ore of lead and an important source of silver. Galena is also one of the most abundant and widely distributed sulfide minerals. It crystallizes in the cubic system often showing octahedral forms. It is often associated with the minerals sphalerite, calcite and fluorite.

The Rogerley Mine is located in the historic Weardale mining District of Northern England. First discovered in the early 1970s, the Rogerley Mine is the only mine in all of Britain to be worked on a commercial scale in the name of collecting crystallized mineral specimens. Since the summer of 1999, UK Mining Ventures has operated the Rogerley Mine on a seasonal basis, producing many fine, well crystallized specimens of green fluorite. Rogerley material is considered some of the finest fluorite in the world, and much of it has incredible fluorescent properties under both daylight and ultraviolet light.
Fluorite & Galena
Rogerley Mine, County Durham, England
4.9" long, 3.1" wide