Bilinite is an iron sulfate mineral

Sulfate mineral

The sulfate minerals are a class of minerals which include the sulfate ion within their structure. The sulfate minerals occur commonly in primary evaporite depositional environments, as gangue minerals in hydrothermal veins and as secondary minerals in the oxidizing zone of sulfide mineral deposits...

. It is a product of the oxidation of pyrite

Pyrite

The mineral pyrite, or iron pyrite, is an iron sulfide with the formula FeS2. This mineral's metallic luster and pale-to-normal, brass-yellow hue have earned it the nickname fool's gold because of its resemblance to gold...

 in water. It is an acidic mineral

Mineral

A mineral is a naturally occurring solid chemical substance formed through biogeochemical processes, having characteristic chemical composition, highly ordered atomic structure, and specific physical properties. By comparison, a rock is an aggregate of minerals and/or mineraloids and does not...

 that has a pH of less than 3 and is harmful to the environment when it comes from acid rock drainage (Keith et. al., 2001).

Bilinite was first discovered near Bilina, Czech Republic

Czech Republic

The Czech Republic is a landlocked country in Central Europe. The country is bordered by Poland to the northeast, Slovakia to the east, Austria to the south, and Germany to the west and northwest....

 which is why the mineral

Mineral

A mineral is a naturally occurring solid chemical substance formed through biogeochemical processes, having characteristic chemical composition, highly ordered atomic structure, and specific physical properties. By comparison, a rock is an aggregate of minerals and/or mineraloids and does not...

 was named 'bilinite' (Palache, et al., 1969). This mineral possibly occurs on Mars

Mars

Mars is the fourth planet from the Sun in the Solar System. The planet is named after the Roman god of war, Mars. It is often described as the "Red Planet", as the iron oxide prevalent on its surface gives it a reddish appearance...

.

Composition

The weight percent oxide is as follows:

Oxide	Composition
SO3	33.78
Fe2O3	16.84
FeO	7.58
H2O	41.8
Total	100

Related minerals

Related minerals to bilinite include jarosite

Jarosite

Jarosite is a basic hydrous sulfate of potassium and iron with a chemical formula of KFe3+362. This sulfate mineral is formed in ore deposits by the oxidation of iron sulfides...

, which is an iron sulfate salt, lepidocrocite

Lepidocrocite

Lepidocrocite , also called esmeraldite or hydrohematite, is an iron oxide-hydroxide mineral. Lepidocrocite has an orthorhombic crystal structure, a hardness of 5, specific gravity of 4, a submetallic luster and a yellow-brown streak. It is red to reddish brown and forms when iron-containing...

, schwetmannite, ferricopiapite, and copiapite (Marion, et. al., 2008).

Special characteristics

Boulder Creek

Boulder Creek

Boulder Creek may be:*A community:**Boulder Creek, California*One of several streams:**Boulder Creek in Santa Cruz County**Boulder Creek in San Diego County**Boulder Creek **Boulder Creek...

 is a stream at Iron Mountain

Iron Mountain

-United States:Communities* Iron Mountain, Shasta County, California* Iron Mountain, Michigan, a city* Iron Mountain, Missouri, a community and historic mining area in St...

 in Shasta County, California

Shasta County, California

Shasta County is a county located in the northern portion of the U.S. state of California. The county occupies the northern reaches of the Sacramento Valley, with portions extending into the southern reaches of the Cascade Range. As of the 2010 census, the population was 177,223, up from 163,256...

. The stream drains into the Sacramento River

Sacramento River

The Sacramento River is an important watercourse of Northern and Central California in the United States. The largest river in California, it rises on the eastern slopes of the Klamath Mountains, and after a journey south of over , empties into Suisun Bay, an arm of the San Francisco Bay, and...

 and San Francisco Bay

San Francisco Bay

San Francisco Bay is a shallow, productive estuary through which water draining from approximately forty percent of California, flowing in the Sacramento and San Joaquin rivers from the Sierra Nevada mountains, enters the Pacific Ocean...

. The water in this stream is contaminated from the mixture of the groundwater and surface streams due to mining

Mining

Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...

. The pH

PH

In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...

 is low and acidic due to the oxidation of pyrite in water. This results in the formation of sulfuric acid

Sulfuric acid

Sulfuric acid is a strong mineral acid with the molecular formula . Its historical name is oil of vitriol. Pure sulfuric acid is a highly corrosive, colorless, viscous liquid. The salts of sulfuric acid are called sulfates...

and bilinite (Keith, et al., 2001).