Marble Thin Section

4j shows a very fine grained calcite marble with occasional anisotropic fabric due to calcite layering.

Marble thin section.

The thin section of gray sample gtb 5 table 1 and fig. In thin section the sample can be seen to contain abundant rounded and sometimes deformed dark crystals of pyroxene diopside and hornblende within a fine grained crystalline carbonate groundmass. This process generally increases the average grain size which gives marble its sparkling appearance. It also displays a slightly foliated microstructure with grain size variations in irregular bimodal bands.

The first is extremely fine with signs of dynamic recrystallization and the second. Some common rock types as seen under the microscope. In this photo the thin section was rotated to obscure twinning. These are photomicrographs very thin slices of rock seen in plane polarised light or between crossed polarisers when the colours seen are produced by interference of light.

Tremolite marble the term marble in geology is restricted to metamorphic rocks in which the carbonate minerals have recrystallized. The somewhat less altered and narrower albite exsolution lamellae are in sharp contact with larger microcline domains. The word marble derives from the greek màrmaron crystalline rock shining stone. A becke line test tells you which phase is which.

Microstructure and grain size measurements on thin sections of this marble identify two petrographic varieties. Rocks under the microscope. This marble is one of several prominent pink coloured bands that have been used as a decorative stone. Perthite from a metaluminous biotite granite.