Black tea is made from the leaves of a bush called Camellia sinensis. A process called oxidation turns the leaves from green to a dark brownish-black color. Oxidation means the leaves are exposed to moist, oxygen-rich air.
Marble is a non-foliated metamorphic rock composed of recrystallized carbonate minerals, most commonly calcite or dolomite. Geologists use the term marble to refer to metamorphosed limestone; however, stonemasons use the term more broadly to encompass unmetamorphosed limestone.Marble is commonly used for sculpture and as a building material.eologists use the term marble to refer to metamorphosed limestone; however, stonemasons use the term more broadly to encompass unmetamorphosed limestone.
Marble is a metamorphic rock which is a product of natural exposure deep underground to intense heat and pressure on limestone or dolostone, both sedimentary rocks.The minera â¦ ls calcite or dolomite that are present in the limestone or dolostone are recrystallized, causing them to be larger and interlocked.arble forms when calcium-rich rock like limestone is exposed to high heat and pressure. 9 people found this useful. Edit. Share to: 1  Characteristics and Common Uses of Marble Rock The metamorphic rock marble is simply limestone that has been near a large amount of heat and pressure.