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Abstract
Carbonate formation are discussed from all published mineral compositions and the X-ray fluorescence (XRF) analyses with contents of carbon and other foreign elements. New formation of metamorphic calcite minerals are discussed by these elements with the XRF data of present sea-shells, transparent calcite crystal and aragonite, and coloured calcites (grey, red and green) and marble-stones of European and Middle-East countries used for wall-stones. Mineral characteristics of these foreign elements of Na, Mg, Al, Si, P, S, Cl, K and Fe, replaced in Ca and C, in calcite-carbonates are considered to be new indicator of these formations at their circumstances (such as sea-floor or sea-surface, rocks of plate-tectonics or meteoritic metamorphism at the crustal rocks).
Key words: carbonates, calcite, marble-stones, carbon, trace elements, XRF analyses
Introduction
Carbonate minerals are considered to be sedimentary rocks by the following reaction:
1. Fossil (Ca) relicts with carbonate ion (CO2) by chemical reaction during sedimentation.
2. Chemical re-crystallization after original carbonates, such as limestone cave formation by underground water (as stalactite and stalagmite and staracmite) (Miura, 2006 a,b, 2007a,b, 2008a,b). Recently it was pointed out that there is a third way of calcite carbonates formation - throughout a metamorphic process (French, 1998; Miura, 2007a,b, 2008a,b; Miura and Tanosaki, 2009).
The main purpose of the present paper is to make clear the main mineral composition of carbonates from published and collected minerals with minor elements as metamorphic formation process.
Mineral compositions with carbon and other elements
From published mineral compositions (University of Sheffield, 2006; Miura, 2008 a,b), most of the carbon (C) element in all minerals (210 C-bearing minerals with more than 5%C) is combined (61% in all carbon-bearing minerals) as three (66 minerals, such as CaCO3) or four (63 minerals, such as dolomite) elements in each mineral composition (fig. 1). This indicates that carbon element forms almost all mineral composition together with three or four other elements on the Earth.
Carbon-bearing mineral compositions with three elements
From published mineral compositions (University of Sheffield, 2006; Miura, 2008 a,b), carbon-bearing minerals with three other elements form 180 minerals with 24 type of elements involved in the combination (except C) as shown in figure 2. This indicates that carbon C is easily combined with oxygen O (35% in 180 minerals) to...