Barićite

Chemical formula: (Mg,Fe₂+)₃(PO₄)₂·₈H₂O

Barićite is a hydrated magnesium and iron phosphate, forming colorless or pale blue, tabular crystals, closely related to vivianite.

## Characteristics Barićite is a member of the vivianite group, forming an isomorphic series with it. It occurs as well-formed, tabular or prismatic crystals, often gathered in radial or fan-shaped aggregates. Specimens are usually small, rarely exceeding a few centimeters. This mineral is transparent to translucent and is characterized by a vitreous luster, and a pearly luster on cleavage surfaces. ## Physical Properties Barićite is a relatively soft mineral with a hardness of 1.5-2 on the Mohs scale, meaning it can be scratched with a fingernail. Its density is approximately 2.61 g/cm³. It has perfect cleavage in one direction, which causes it to easily split into thin, flexible lamellae. This is a characteristic feature of the entire vivianite group. ## Colors and Varieties The most common specimens are colorless, white, or pale blue. Some crystals may exhibit slight pleochroism, which is a change in color hue depending on the observation direction. No named varieties of barićite are distinguished. ## History and Name The mineral was named in 1976 in honor of Dr. Ljubica Barić (1914-1995), a long-time curator and director of the Mineralogical-Petrographic Museum in Zagreb, in recognition of her contribution to mineralogy. It was discovered and described based on material from Big Fish River in Yukon, Canada. ## Uses Barićite has no industrial applications. Its significance is purely scientific and collectible; it is valued by collectors specializing in rare phosphate minerals and systematic minerals.

Properties

Mohs hardness: 1.5-2
Luster: Vitreous, Pearly
Streak: White
Density: 2.61
Cleavage: Perfect on {010}
Fracture: Uneven
Transparency: Transparent to translucent
Crystal system: Monoclinic

Diagnostic features

## Identification A key diagnostic feature of barićite is its perfect cleavage in one direction, which allows for the separation of thin, flexible lamellae. Other important features include low hardness (it can be scratched with a fingernail), characteristic tabular crystal habit, and pearly luster on cleavage planes. It often occurs in the form of radial aggregates. ## Distinguishing from Similar Minerals Barićite is most commonly confused with other minerals from the vivianite group. It is usually distinguished from vivianite by its lighter color (colorless to pale blue, whereas vivianite is often dark blue or green) and lower density. Vivianite darkens upon exposure to light, which is not observed to the same extent in barićite. It is distinguished from gypsum by its crystal form and occurrence environment. However, definitive differentiation requires advanced chemical (EDS) or X-ray (XRD) analyses. ## Crystal Forms Barićite crystals are monoclinic, with a distinctly tabular habit, flattened parallel to the perfect cleavage plane. They often form fan-shaped, radial, or nearly spherical aggregates. They also occur as rosettes and clusters of parallel-oriented crystals.

Geological environment

## Genesis Barićite is a secondary mineral, forming in the oxidation zones of phosphate deposits. It forms under low-temperature conditions, often in vugs and fissures in sedimentary rocks, such as sideritic iron clays. Its formation is associated with the activity of phosphate-rich solutions reacting with magnesium and iron-bearing minerals. ## Mineral Associations This mineral often co-occurs with other phosphates. In its type locality (Big Fish River), it was found in association with satterlyite, maricite, quartz, ludlamite, vivianite, and pyrite. In other localities, it may occur with siderite and other iron minerals. ## Localities The most important and type locality for barićite, from which the best specimens originate, is the area along the Big Fish River and Rapid Creek in the Dawson mining district in Yukon, Canada. This is the classic and practically only commercially significant locality for this mineral. It has also been identified in very small quantities in the Cirque of the Unclimbables in the Northwest Territories, Canada.

Rarity

Rare

For collectors

## Quality Criteria The most prized barićite specimens are characterized by sharply terminated, well-formed crystals with high transparency and an attractive, pale blue color. Particularly sought after are radial aggregates forming complete "suns" or fans, aesthetically set on a small rock matrix. The size of the crystals and entire aggregates also significantly affects the value, as does the absence of damage, which is common due to the mineral's fragility. ## Popular Localities The vast majority, if not all, collectible barićite specimens on the market come from one area: Big Fish River / Rapid Creek in Yukon, Canada. Material from this locality is considered the global standard for this species.

Care and storage

## Cleaning Barićite specimens should be cleaned with the utmost care due to their softness and perfect cleavage. The safest method is to use compressed air to remove dust. If wet cleaning is necessary, use only distilled water and a very soft brush, avoiding any pressure. After cleaning, the specimen should be dried immediately and thoroughly. ## What to Avoid Ultrasonic cleaners, which can destroy crystals, must be absolutely avoided. The mineral is sensitive to chemicals, so contact with acids, bases, and detergents should be avoided. It should not be heated or exposed to prolonged strong sunlight. Due to the presence of iron, prolonged exposure to moisture and air can lead to oxidation and color change. ## Storage Barićite is very brittle and soft, so it should be stored separately, in a padded box, away from harder minerals that could scratch it. It is not suitable for display in areas with fluctuating humidity or temperature.

Sources

IMA Mineral List (CNMNC)