THE MINERAL VILLIAUMITE
- Chemistry: NaF, Sodium Fluoride
- Class: Halides
- Group: Halite
- Uses: Rarely cut as gemstones
and as mineral specimens.
Villiaumite is another strongly colored
It has a typically bold red "carmine" color that is visually unique.
Other colorful halides include
also green, yellow, etc),
(blue) to name a few.
Villiaumite's color ranges from the strong red to reddish orange, to lavender pink.
It is commonly found with colorless edges or portions that transition into the strongly
colored portions of the crystal.
Fluorescence is observed in many specimens, but is generally only a weak red color under
both short and longwave ultraviolet light.
Villiaumite was named for the French explorer: Villiaume.
Although he did not techically discover the mineral; he did collect some rock samples from Guinea in which the new mineral villiaumite was found.
Villiaumite is a rare mineral and is found in only a few localities.
Most massive specimens are coming from the
Kola Peninsula where the mineral is
associated with many other rare russian minerals such as
Another great locality for villiaumite is
Quebec, Canada where fine crystals are found.
Some crystals from here have been cut as
but villiaumite is NOT a gemstone mineral as it is too soft and is not durable at all.
In fact, villiaumite is
soluble in water.
Not exactly a property one looks for in a gemstone!
Villiaumite is a sodium salt and those salts are usually soluble.
And for this reason a desicant should be placed with any specimen to avoid moisture absorbtion and thus its possible destruction.
Villiaumite is a nice mineral to own.
It has excellent crystal form (mostly cubes and octahedrons) and is often
associated with rare and interesting minerals.
Its color is unique and often bright and bold.
With rarity, color, associations, fluorescence and crystal form, villiaumite
has a lot going for it!
- Color is carmine red to reddish orange and lavender pink to pink.
Most specimens show some colorless areas.
- Luster is vitreous to waxy in massive specimens.
- Transparency: Crystals are transparent to translucent.
- Crystal System is isometric; 4/m bar 3 2/m.
- Crystal Habits include small cubes, cubo-octahedrons and octahedrons.
Also found massive and as void-filling grains.
- Cleavage is perfect in three directions forming cubes.
- Fracture is conchoidal.
- Hardness is 2 - 2.5.
- Specific Gravity is 2.8 (average)
- Streak is pinkish white.
- Other Characteristics: The
index of refraction is 1.327, specimens are
soluble in water and some specimens weakly
fluoresce a red color under UV light.
- Associated Minerals include
murunskite among others.
- Notable Occurrences include the type locality: Rouma, the Islands of Los,
Guinea as well as the Khibina Massif,
Russia; Aris, Namibia; Point of Rocks, Colfax County, New Mexico, USA;
Quebec, Canada and Greenland.
- Best Field Indicators are crystal habit, color, solubility in water,
occurrence, fluoresce and associations.