Marble alteration

Limestone varieties differ greatly from one another in their texture and the impurities they contain, and consequently they also differ in color. The color of limestone may vary from white (when it contains practically no impurities) to off-white and even to intensely colored. Minor inclusions within the limestone structure are often of silica, usually in a concentration below 5%, as well as feldspar and clay in still lesser amounts. Many types of limestone also include embedded fossils. Much limestone deposits in the outer crust of the earth are altered during geologic metamorphic processes that involve mainly pressure and heat but also liquids and gases. Marble, for example, a metamorphic rock derived from calcium carbonate, is white when composed only of this substance colored metal ions and other impurities impart to marble a wide range of colors such as red, yellow, and green and also give... 

Acid rain harms the environment in a number of ways it dissolves many rocks and metals, alters the composition of soils, groundwaters, and lakes, and alters the environmental conditions of living organisms. Acid rain is also particularly harmful to ancient objects and structures, as it plays an important role in their deterioration and sometimes total destruction. Unprotected limestone, marble, and sandstone, all of them widely used in ancient times for building and making statuary, are disintegrated by acid rain, which... 

Ague J. J. and van Haren J. L. M. (1996) Assessing metasomatic mass and volume changes using the bootstrap, with application to deep crustal hydrothermal alteration of marble. Econ. Geol. 91, 1169—1182. 

Solids aren t really solid They are mostly empty space When we discuss the structure of an atom in Chapter 3 you will learn that the size of the nucleus is actually very tiny compared to the size of the atom. The space that an atom effectively occupies really has to do with the fact that the electrons are moving very quickly and that the repulsive forces between electrons of different atoms keep them a certain distance apart. If you could strip the electrons off an atom and neutralize the charge of the nucleus, the atom would occupy only a fraction of its original size. To picture the size change, if the original size of the atom was about the size of a baseball stadium, the altered atom would be about the size of a marble. Just think The solid floor that you stand on is almost completely empty space ... 

Youngdahl, C. A. Doe, B. R. Sherwood, S. I. Roughening Recession and Chemical Alteration of Marble and Limestone Sample Surfaces After Atmospheric Exposure in the Northeastern United States. In this book. 

YOUNG DAHL AND DOE Chemical Alteration of Marble and Limestone... 

Figure 2. Dimensions of wedge-shaped briquettes employed as specimens of marble and limestone. Also shown are locations of areas sampled in layers to assess depth of chemical alteration caused by atmospheric exposure.

Metamorphic rocks are either igneous or sedimentary rocks that have been altered by the action of pressure or heat. Marble is an example of a metamorphic rock, being limestone whose crystalline structure has been altered by pressure or heat. Metamorphic rocks tend to be more resistant to weathering agents than the original sedimentary rocks. The almost total loss of pore space and structure reduces the ability of weathering agents to enter the material. 

As typical water-contained karst water mine, Gujiatai Eon Mine is characterized with complicated hydrogeological conditions, a river cuts through middle of the ore body on the earth s surface and there are mainly two aquifers, which are quaternary glutenite and Ordovician system limestone developed from karst, and tertiary aquiclude between the two aquifers. The ore body lies in contact zone of marble and diorite and presents stratoid. Direct roof of ore body is mostly marble and its footwall is skam, sometimes skarnized diorite and alteration diorite. 

The Selbome Marble in Table 5.1 consists of highly deformed and metamorphosed scapolite-bearing marbles interbedded with biotite schist and homfels that occur only at Cape Selbome and at the north side of Couzens Bay, both of which are located south of the mouth of the Byrd Glacier. The relation of the Selbome Marble to the Shackleton Limestone is uncertain because the two units are not in contact. Skinner (1964, 1965) suggested that the Selbome Marble is either a highly altered part of the Shackleton Limestone or is a marble-amphibolite complex of the Precambrian Nimrod Group. Stump (1980) who worked on the Shackleton Limestone at nearby Mount Madison favored the explanation that the Selbome Marble is a highly metamorphosed member of the Shackleton Limestone. 

The overlying Taylor Formation consists of ashfall and ashflow tuffs, felsic and mafic lava flows, and marbles. Wade and Cathey (1986) placed the contact of the Taylor Formation with the underlying Greenlee Formation at about 6 km south of the northern tip of Mt. Greenlee (Fig. 5.16). The contact is obscured by the brecciation and hydrothermal alteration of the Greenlee Formation manifested by the crystallization of epidote. 

Mosaic mo- za-ik [ME musycke, fr. MF mosaique, fr. Olt mosaico, fr. ML musai-cum, alter, of LL musivum, ff. L museum, musaeum] (15c) n. (1) Picture or surface decoration made by embedding small pieces of colored stone, marble, pottery, or glass in mortar. 

Ciliberto and al. used XPS to study the penetration depth of the products introduced by Sanpaolesi s treatment in the marble matrix of the Donatello pulpit. The masterpieces of the famous Italian sculptor were in fact restored with a mixture of ZnSiFe and MgSiFe in 1941. The surface analysis showed that both the fluoride- and silicon-containing compoimds enrich the most external layers of the marble. Two small fragments, about 1.0-0.5cm wide and <0.5cm thick, were studied fi om a chemical point of view and replaced to their original position after the study in an attempt to minimize any damage or alterations to the work of art as awhole[48]. 

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