Chemical Characteristics of Ohio Minerals

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Elements in Ohio Minerals

The chemical components of minerals are elements and elemental groups. An "element" is a distinct variety of matter, which by itself or in combination with other elements, make up substances of many kinds. For example, gold is an element. It also is substance that is familiar to many people. The substance called gold is made up almost entirely of the element that also is called gold. Therefore, when we speak of the mineral gold, we call it "elemental gold." This means that it consists of just one element, gold, rather than a combination of elements. On the other hand, the mineral pyrite consists of two elements: iron and sulfur. When we speak of this mineral we call it just "pyrite." The major chemical elements that are found in Ohio’s minerals are as follows:


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Element Symbol
aluminumAl
magnesiumMg
bariumBa
manganeseMn
calcium
Ca
nickelNi
carbonC
oxygenO
chlorineCl
phosphorusP
chromiumCr
potassiumK
copperCu
siliconSi
fluorineF
sodiumNa
goldAu
strontiumSr
hydrogenH
sulfurS
ironFe
titaniumTi
leadPb
zincAn

Elemental Groups in Ohio MineralsAn "elemental group," however, consists of more than one element. Elemental groups do not exist by themselves. Rather, in combination with other elements they make up substances such as minerals. Sulfur and oxygen together in the proper combination make up what is known as the "sulfate" elemental group. This group, in combination with the element barium, form the mineral barite. The major elemental groups that are found in Ohio’s minerals are as follows:

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Elemental Group Symbol Elements
carbonateCO3carbon and oxygen
oxalateC2O4carbon and oxygen
phosphatePO4phosphorus and oxygen
silicate (hemimorphite type)Si2O7silicon and oxygen
silicate (mica & clay type)Si4O10silicon and oxygen
silicon dioxide
SiO2silicon and oxygen
sulfite
SO4sulfur and oxygen
waterH2Ohydrogen and oxygen

Mineral Classes

Most of the minerals in our world have precise chemical structures. For example, the mineral pyrite consists of one part of iron with two parts of sulfur. We write the formula for this mineral as "FeS2" using "Fe" to indicate iron and "S" to indicate sulfur. The mineral galena has sulfur in its structure also, but it has the metal lead instead of iron. We write its formulas as "PbS" to indicate one part of lead (Pb) with one part of sulfur (S). And so it goes, with each mineral having a chemical formula which reflects its chemical constituents. Because of this consistency in chemical structure it is possible to classify or group minerals. Mineralogists have done just that in order to make it easier to study and understand the wide diversity of minerals, and to understand the relationships between minerals. Following are the chemical classes of Ohio’s minerals:

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Chemical Class Character Examples
native elementssingle elements, uncombinedsulfur (S)
sulfideselemental sulfur (S) combined with different metalspyrite (FeS2)
oxideselemental oxygen (O) combined with different metalshematite (Fe2O3)
halideselemental fluorine (F) or chlorine (Cl) combined with different metalsfluorite (CaF2)halite (NaCl)

See Also