Petrographic classification

Image analysis of stained slabs (Duncan 1999) indicates these rocks should probably be referred to as ( ) augite syenite, ( ) hornblende quartz syenite, and ( V) biotite syenogranite (from mean petrographic classification Fig. 2). 

Hower, J. C. Mastalerz, M. 2001. An approach toward a combined scheme for the petrographic classification of fly ash. Energy and Fuels, 15, 1319-1321. 

Hutton, A. C. 1987. Petrographic classification of oil shales. International Journal of Coal Geology, 8, 203-231. 

Folk R.L. (1959) Practical petrographic classification of limestones. AAPG Bull. 43, 1-38. 

The relation between chemistry and petrography, the science of the classification of rocks, was somewhat closer since chemical composition was thought by some petrographers to offer a basis for rational classification. But early efforts to categorize rocks by their chemical composition were frustrated as it was discovered that it was impossible to find simple chemical formulas for these bodies. Rocks of different mineral composition fell into the same chemical categories, and rocks that were chemically alike were sometimes quite different in structure, texture, and field relations. Moreover, the success of H. Clifton Sorby s technique for the microscopic study of thin sections of rocks accentuated the tendency to identify rocks on the basis of external rather than internal properties (14, 15). 

Kallemeyn, G. W., Rubin, A. E., Wang, D. and Wasson, J. T. (1989) Ordinary chondrites bulk composition, classification, lithophile-element fractionations, and composition-petrographic type relationships. Geochimica et Cosmochimica Acta, 53, 2747-2767. 

At present, a petrographic combustion correlation is being worked out which should provide ultimately a general classification of coals for use in several combustion processes. The results of this study will be reported at a later date. 

Chondrites are classified into petrologic (or petrographic) types 1-6 to provide a guide to the extent and nature of asteroidal processing. This classification scheme, which has been invaluable (Anders and Kerridge, 1988), nevertheless... 

In the Polish standard PN-87/B-01 1000 the classification, names and determination of particular types of aggregates are given. In the PN-EN 932-3 standard the simplified method of aggregate petrographic constitution verification is recommended, and eventually the chemical composition analyzing. In the PN-G-11010 Polish standard the methods of some hazardous components determination in water leachates are given. Finally, in the PN-EN 1744 standard a group of methods of harmful components (chlorides, fluorides, sulphates), as well as the reactive silica determination is recommended. 

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