Marble Thin Section

Different select categories of rock specimens.

Marble thin section.

The word marble derives from the greek màrmaron crystalline rock shining stone. This process generally increases the average grain size which gives marble its sparkling appearance. Perthite from a metaluminous biotite granite. In this photo the thin section was rotated to obscure twinning.

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. It also displays a slightly foliated microstructure with grain size variations in irregular bimodal bands. Rocks under the microscope. The thin section of gray sample gtb 5 table 1 and fig.

Tremolite marble the term marble in geology is restricted to metamorphic rocks in which the carbonate minerals have recrystallized. When minerals rocks and fossils cannot be accurately identified by macroscopic observation and testing thin section slides can reveal the composition and structure of the specimens on a microscopic level rock specimens are useful for studying textures grain sizes and other features altered by pressure temperature and other natural forces. 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. This marble is one of several prominent pink coloured bands that have been used as a decorative stone.

Some common rock types as seen under the microscope. Microstructure and grain size measurements on thin sections of this marble identify two petrographic varieties. A becke line test tells you which phase is which. The first is extremely fine with signs of dynamic recrystallization and the second.