Short answers, pulled from the story.
Marble is a metamorphic rock that allows light to penetrate its surface through subsurface scattering, creating a lifelike glow. This optical property enables light to travel 12.7 to 38 millimeters into the stone before being scattered back out, giving sculptures a waxy, translucent appearance that mimics human skin.
Marble formed when pure limestone or dolomite was subjected to intense heat and pressure, recrystallizing the original grains into an interlocking mosaic. The colorful veins and swirls result from impurities such as clay, silt, sand, iron oxides, or chert that were mobilized and recrystallized during geological transformation.
A dramatic increase in the distribution of white marble occurred from the late 1st century BC to the end of the 2nd century AD as the Roman Empire expanded. This distribution began to decline in the third century AD as the empire fractured and the logistical challenges of moving such heavy materials became insurmountable.
Particulate air pollution exposure in the marble production industry can impair lung function or cause silicosis, a debilitating lung disease. The Occupational Safety and Health Administration has set the legal limit for marble exposure at 15 milligrams per cubic meter of total exposure and 5 milligrams per cubic meter of respiratory exposure over an 8-hour workday.
China and Italy led global marble production in 2018, representing 34 percent and 19 percent of world output respectively. Turkey emerged as the world leader in marble export in 2018 with a 42 percent share in global marble trade, followed by Italy with 18 percent and Greece with 10 percent.
Famous marble landmarks include the Taj Mahal in India, the Marble Boat in Beijing, and the Elgin Marbles from the Parthenon in Athens displayed in the British Museum. Cities named after the stone include Marblehead, Massachusetts; Marblehead, Ohio; Marble Arch, London; and Ashgabat, the capital city of Turkmenistan.