Secondary Minerals

Secondary Minerals


minerals formed by the chemical disintegration or displacement of minerals evolved earlier. The formation of secondary minerals is common in nature, especially in the surface zones of the earth’s crust during the processes of hypergenesis, and is also linked to changes in the physicochemical parameters of mineral formation.

The transition into secondary minerals can occur without a change in the quality of the composition of the substance— for example, the transition of chalcopyrite CuFeS2 into the secondary bornite CuFeS4. More frequently, however, transition is accompanied by the removal and exchange of substance from the surrounding medium—for instance, the formation of covellite Cu2S CuS2 through chalcopyrite, malachite Cu2[CO3](OH)2 through atacamite CuCl2 3Cu (OH)2, and kaolin through feldspar. Secondary minerals can also be formed during a purely physical change in the crystalline structure of a substance, retaining its chemical composition: cubic chalcosine changes to rhombic chalcosine, high-temperature cubic leucite changes to low-temperature rhombic leucite.

There are various forms of secondary minerals. These are powdery or other masses or pseudomorphs which retain the external form of the primary mineral while the substance is replaced by a new one.


Lazarenko, E. K. Osnovy geneticheskoi mineralogii. L’vov, 1963.


References in periodicals archive ?
Albite Beryl Covellite Gahnite Fluorapatite Digenite Lithiophilite Gahnite Galena Spessartine Manganocolumbite Hessite Triplite Microcline Triploidite Muscovite Secondary Triphylite Pyrochlore Minerals UK-1 Quartz Chrysocolla Zircon Rutile (niobian) Malachite Schorl UK-2 Secondary Phosphates Spessartine Crandallite Spodumene Eosphorite Uranmicrolite Fluorapatite Uranpyrochlore Zircon Secondary Minerals Coronadite Hectorite
A chapter deals with the famous iron deposits and the surrounding skarns in the eastern part of the island: Rio Marina, Capo Calamita and several others, which have produced the classic hematites, pyrites, ilvaites and a number of less common species and secondary minerals.
It often lacks the secondary minerals that occur on Earth due to weathering and igneous-water interactions.
The mafic dykes are porphyritic to aphyric and consist of calcic plagioclase, hornblendic amphibole or clinopyroxene +/- olivine, ilmenite, titanite and a range of secondary minerals.
The financing proposal by GSFC to KRN permitted the spin-out of certain undeveloped lands into a new public company to pursue all secondary minerals other than potash.
The superficial mineralization are mostly oxidized in the surface and in the study of the sections a great volume of metamorphosed sulfite minerals are seen, so that healthy chalcopyrite is seen in the form of remaining among oxides and iron hydroxides and they are dissolved to secondary minerals of chalcocite and covelite (figure 11).
The secondary minerals include limonite, copper greens, azurite.
An integrated energy dispersive analyzer (EDS) was used to determine the composition of the secondary minerals formed in the pore space of the material.
The sampling strategy consisted of taking samples containing natural zeolites and other secondary minerals filling in amygdales and veins from several outcrops in fresh road cuts and new quarries along the roads Petrographical and microscopy studies were made of specimens of zeolite-bearing rocks to identify mineral species; this led to clarifying and confirming field observations A trinocular Nikon (Labophot2-POL) transmitted light microscope was used to observe the minerals' optical properties in thin sections.
The process can be observed in action even today, as primary sulfide deposits are altered by weathering into much more complex suites of secondary minerals with longer formulas.
Standard acid digestions do not readily dissolve the larger crystalline aluminosilicates, but would be expected to readily dissolve metastable and stable secondary minerals, the ultra-fine hydrated oxide films, and other amorphous forms of these elements.

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