Economic Geology Ores

Barite is a mineral composed of barium sulfate (BaSO4). The chemical formula BaSO4 represents the combination of one barium ion (Ba2+) and one sulfate ion (SO42-). This formula accurately represents the composition of Barite, making it the correct answer.

The chemical formula for Chalcopyrite is CuFeS2. This formula represents the composition of the mineral, indicating that it consists of one copper (Cu) atom, one iron (Fe) atom, and two sulfur (S) atoms. Chalcopyrite is a common copper mineral and is often found in copper ores. Its chemical formula is derived from the elements present in its crystal structure.

Pyrite is a mineral commonly known as "fool's gold" due to its resemblance to gold. Its chemical formula is FeS2, which indicates that it is composed of one iron (Fe) atom bonded to two sulfur (S) atoms. This formula represents the ratio of elements present in the compound, indicating that each pyrite molecule contains one iron atom and two sulfur atoms.

Magnetite is a mineral that is composed of iron and oxygen. Its chemical formula is Fe3O4, which indicates that it contains three iron atoms and four oxygen atoms. This formula accurately represents the composition of magnetite, making Fe3O4 the correct answer.

Molybdenite is a naturally occurring mineral that consists of molybdenum disulfide (MoS2). Therefore, the chemical formula for Molybdenite is MoS2.

Bornite is the correct answer because it has the chemical formula Cu5FeS4. Bornite is a copper iron sulfide mineral that is commonly found in copper deposits. It is known for its iridescent colors, which can range from purple to blue to copper-red. Bornite is an important ore of copper and is often used in the production of copper metal.

The chemical formula for Arsenopyrite is FeAsS. This means that Arsenopyrite is composed of iron (Fe), arsenic (As), and sulfur (S) elements. The formula indicates that there is one atom of iron, one atom of arsenic, and one atom of sulfur in each unit of Arsenopyrite.

The description "Peacock blue to purple" best describes Bornite. Bornite is a copper ore mineral that exhibits a wide range of colors, including shades of blue and purple. Its iridescent colors are reminiscent of the vibrant hues seen on a peacock's feathers. Therefore, Bornite is the mineral that matches the given description.

Hematite is not magnetic. Although it is an iron oxide mineral, it does not possess magnetic properties. The confusion may arise from the fact that hematite can sometimes be found near magnetic minerals or be attracted to magnets due to impurities or inclusions. However, pure hematite itself does not exhibit magnetic behavior. Hence, the correct answer is False.

The chemical equation of Chromite is FeCr2O4. This formula represents the composition of the compound, where Fe represents iron, Cr represents chromium, and O represents oxygen. The subscript numbers indicate the number of atoms of each element in the compound. Therefore, FeCr2O4 is the correct chemical equation for Chromite.

Azurite is commonly associated with two minerals: Malachite and Cuprite. Malachite is a green mineral that often occurs alongside Azurite, forming a unique combination of blue and green colors. Cuprite, on the other hand, is a red mineral that can also be found in association with Azurite. These two minerals often occur together in the same geological formations, making them commonly associated with Azurite.

The chemical formula for Pyrrhotite is Fe1-xS. This means that Pyrrhotite is composed of iron (Fe) and sulfur (S), with the ratio of iron to sulfur represented by the variable x. The formula indicates that the compound can have varying amounts of iron, as x can range from 0 to 1.

The chemical formula for Wolframite is (Fe,Mn)WO4. This formula indicates that Wolframite is composed of iron (Fe), manganese (Mn), tungsten (W), and oxygen (O). The presence of both iron and manganese in the formula suggests that Wolframite can have varying compositions, with either element or a combination of both being present. The addition of the subscript 4 indicates that there are four oxygen atoms in the compound.

Bauxite is an ore that is the primary source of aluminum. Its chemical formula is AlO(OH) or Al(OH)3. The correct answer includes all possible representations of the chemical formula for bauxite, which are AlO(OH)/Al(OH)3, AlO(OH) or Al(OH)3, AlO(OH), Al(OH)3, and AlO(OH) / Al(OH)3.

Nickeline is a mineral that is typically pink in color. It is also known as niccolite and is a nickel arsenide. The pink hue of nickeline is due to the presence of nickel in its composition. While it can sometimes appear silver or grayish, the predominant color is pink, making it a distinctive characteristic of this mineral.

Stibnite is a mineral that can be described as acircular, silvery, and having growth lines perpendicular to its long axis. The term "acircular" suggests that it does not have a circular shape, while "silvery" refers to its shiny, metallic appearance. Additionally, the statement about crystals having growth lines perpendicular to the long axis indicates a characteristic feature of stibnite crystals.