Identyfikacja pospolitych minerałów węglanowych przy użyciu wskaźników barwiących
Abstract
IDENTIFICATION OF COMMON CARBONATE MINERALS WITH THE USE OF COLOURING INDICES
Summary
The authors have reviewed various stains diagnostic for the major carbonate rock-forming minerals. Of all previously proposed stains the Alizarine Red S, Harris' Haematoxylin and Feigl's Solution are in the authors' opinion the valuable most for staining. The former stain in general imparts a red coulor to calcite within l-2 minutes whereas dolomite is unaffected. Alizarine Red can be used for both microscopic and megascopic examinations. Harris' Haematoxylin brings about the colour change of a drop itself from purple to dark blue within a few seconds for calcite or 2-3 minutes for dolomite.
This stain is recommended in the field studies, especially of dark-coloured rocks. Feigl's Solution imparts a black colour to aragonite only. In addition to this, combined organic and inorganic stains specific for Fe-calcite and Fe-dolomite as well as Choquette and Trusell's Solution (2) for a discrimination between high and low magnesium calcite may be recommended. The visual differentiation between aragonite, calcite and dolomite is of great importance to most basic studies of carbonate rocks in aspects of their genesis and stratigraphic correlation.
Summary
The authors have reviewed various stains diagnostic for the major carbonate rock-forming minerals. Of all previously proposed stains the Alizarine Red S, Harris' Haematoxylin and Feigl's Solution are in the authors' opinion the valuable most for staining. The former stain in general imparts a red coulor to calcite within l-2 minutes whereas dolomite is unaffected. Alizarine Red can be used for both microscopic and megascopic examinations. Harris' Haematoxylin brings about the colour change of a drop itself from purple to dark blue within a few seconds for calcite or 2-3 minutes for dolomite.
This stain is recommended in the field studies, especially of dark-coloured rocks. Feigl's Solution imparts a black colour to aragonite only. In addition to this, combined organic and inorganic stains specific for Fe-calcite and Fe-dolomite as well as Choquette and Trusell's Solution (2) for a discrimination between high and low magnesium calcite may be recommended. The visual differentiation between aragonite, calcite and dolomite is of great importance to most basic studies of carbonate rocks in aspects of their genesis and stratigraphic correlation.