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- https://geo.libretexts.org/Bookshelves/Geology/Mineralogy_(Perkins_et_al.)/07%3A_Sedimentary_Minerals_and_Sedimentary_RocksWeathering involves the decomposition and breaking apart of rocks at Earth’s surface. Products of weathering may be transported and deposited to produce clastic or chemical sediments. Clastic material...Weathering involves the decomposition and breaking apart of rocks at Earth’s surface. Products of weathering may be transported and deposited to produce clastic or chemical sediments. Clastic material typically comprises quartz and clays; less commonly other minerals. We name clastic sedimentary rocks based primarily on clast size. We name chemical sedimentary rocks based primarily on composition.
- https://geo.libretexts.org/Bookshelves/Geology/Mineralogy_(Perkins_et_al.)/02%3A_Mineral_Chemistry/2.02%3A_Elements_and_the_Periodic_Table/2.2.02%3A_Atomic_Number_and_MassZ is also equal to the number of electrons orbiting the nucleus in neutral (non-ionized) atoms, and is close to the number of electrons in most ions. Because the size of its electron cloud controls th...Z is also equal to the number of electrons orbiting the nucleus in neutral (non-ionized) atoms, and is close to the number of electrons in most ions. Because the size of its electron cloud controls the diameter of an atom, elements with greater atomic number, with many protons and thus many electrons, are larger than those or lower atomic number. Mass number, designated by the variable A, is equal to the number of protons and the number of neutrons combined: A = Z + N.
- https://geo.libretexts.org/Bookshelves/Geology/Mineralogy_(Perkins_et_al.)/14%3A_Mineral_Descriptions/14.01%3A_Silicate_Class/14.1.01%3A_Silicate_Class_-_Framework_SilicatesThe structure contains two types of holes for anions and anionic groups: one holds Na and Ca; the other Cl or CO 3 . CaAl substitutes for NaSi freely; SO 4 and F may substitute for Cl and CO 3 . The t...The structure contains two types of holes for anions and anionic groups: one holds Na and Ca; the other Cl or CO 3 . CaAl substitutes for NaSi freely; SO 4 and F may substitute for Cl and CO 3 . The two dominant scapolite end members are marialite, Na 4 (AlSi 3 O 8 ) 3 Cl, and meionite, Ca 4 (Al 2 Si 2 O 8 ) 3 (CO 3 ,SO 4 ).
- https://geo.libretexts.org/Bookshelves/Geology/Mineralogy_(Perkins_et_al.)/04%3A_Crystals_and_Crystallization/4.02%3A_Forming_Crystals/4.2.03%3A_Hydrothermal_MineralsTravertine and tufa, deposited by hot springs, are examples of hydrothermal deposits. Both are composed of calcite that precipitated from hydrothermal solutions, but tufa is more porous than travertin...Travertine and tufa, deposited by hot springs, are examples of hydrothermal deposits. Both are composed of calcite that precipitated from hydrothermal solutions, but tufa is more porous than travertine. Occasionally, hot circulating groundwater deposits minerals in sufficient quantity to make a valuable ore deposit. In some, ore minerals are concentrated in veins or vugs, in others they are disseminated throughout a body of rock. Minerals Common in Hydrothermal Ore Deposits
- https://geo.libretexts.org/Bookshelves/Geology/Mineralogy_(Perkins_et_al.)/11%3A_Crystallography/11.01%3A_Observations_in_the_Seventeenth_through_Nineteenth_Centuriesblank• The building block has shape and symmetry that relate to the shape and symmetry of the entire crystal. Wollaston and others concluded that when crystal shapes in such series are truly identical...blank• The building block has shape and symmetry that relate to the shape and symmetry of the entire crystal. Wollaston and others concluded that when crystal shapes in such series are truly identical, the distribution of atoms within the crystals must be identical as well, even if the compositions are not.
- https://geo.libretexts.org/Bookshelves/Geology/Mineralogy_(Perkins_et_al.)/04%3A_Crystals_and_Crystallization/4.04%3A_Factors_Controlling_Crystal_Size_and_Perfection/4.4.02%3A_Ostwald_RipeningThis means that larger crystals are more chemically stable because molecules in the interior of crystal are less reactive and have lower energy than those on the outside. Consequently, with time, ener...This means that larger crystals are more chemically stable because molecules in the interior of crystal are less reactive and have lower energy than those on the outside. Consequently, with time, energetics trumps kinetics and molecules on the outside of small crystals diffuse and add to the outside of larger ones. The ripening also explains why large crystals (called phenocrysts) surrounded by a sea of small crystals may form in some volcanic rocks.
- https://geo.libretexts.org/Bookshelves/Geology/Mineralogy_(Perkins_et_al.)/02%3A_Mineral_Chemistry/2.04%3A_Bonding_in_Minerals/2.4.04%3A_Other_Kinds_of_BondsBesides the three kinds of bonds just discussed, some minerals include other types of bonds such as van der Waals bonds and hydrogen bonds. Clay minerals have excellent cleavage because covalent and i...Besides the three kinds of bonds just discussed, some minerals include other types of bonds such as van der Waals bonds and hydrogen bonds. Clay minerals have excellent cleavage because covalent and ionic bonds create strongly bonded layers, but weak van der Waals and hydrogen bonds hold the layers together. Because most mineral properties are explained by ionic, covalent, or metallic bonds and we can ignore van der Waals and hydrogen bonds for most purposes.
- https://geo.libretexts.org/Bookshelves/Geology/Mineralogy_(Perkins_et_al.)/12%3A_X-ray_Diffraction_and_Mineral_Analysis/12.02%3A_Obtaining_a_Mineral_AnalysisThe volume of reagent necessary to make the reaction occur is proportional to the amount of the element of interest that is present. The color intensity is proportional to the amount of the element of...The volume of reagent necessary to make the reaction occur is proportional to the amount of the element of interest that is present. The color intensity is proportional to the amount of the element of interest present, which we quantify by comparison to standards. In the 1960s, researchers developed several new kinds of instruments that made mineral and rock characterization and analysis easier, while also providing new and different kinds of information.
- https://geo.libretexts.org/Bookshelves/Geology/Mineralogy_(Perkins_et_al.)/14%3A_Mineral_Descriptions/14.11%3A_Phosphates_Arsenates_and_VanadatesCleavage traces run perpendicular to prism faces and long dimension. (Cleavage is quite obvious in Figure 14.432) Also aiding identification: apatite has moderate density, is softer than quartz and fe...Cleavage traces run perpendicular to prism faces and long dimension. (Cleavage is quite obvious in Figure 14.432) Also aiding identification: apatite has moderate density, is softer than quartz and feldspar, but harder the calcite and fluorite.
- https://geo.libretexts.org/Bookshelves/Geology/Mineralogy_(Perkins_et_al.)/07%3A_Sedimentary_Minerals_and_Sedimentary_Rocks/7.03%3A_Transportation_Deposition_and_Lithification/7.3.01%3A_Clastic_SedimentationStreambed gravel, for example, may contain a mix of silt, sand, and larger clasts, and glacial deposits often contain a jumble of material of many different sizes. Diagenesis is equivalent to a low-te...Streambed gravel, for example, may contain a mix of silt, sand, and larger clasts, and glacial deposits often contain a jumble of material of many different sizes. Diagenesis is equivalent to a low-temperature, low-pressure form of metamorphism, and the processes of sedimentation, lithification, diagenesis, and low-grade metamorphism form a continuum.
- https://geo.libretexts.org/Bookshelves/Geology/Mineralogy_(Perkins_et_al.)Minerals are our planet. They form the Earth and the bedrock that we live on, making up all of Earth’s rocks and sediments, and they are important components in soils. So, they literally are the found...Minerals are our planet. They form the Earth and the bedrock that we live on, making up all of Earth’s rocks and sediments, and they are important components in soils. So, they literally are the foundations for our lives. Perhaps because they are ubiquitous, most people don’t even notice them or consider that all rock is made of minerals.
