Sandstone

Sandstone (disambiguation) is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains. Sandstones comprise about 20–25% of all sedimentary rocks.

Most sandstone is composed of quartz or feldspar (both silicates) because they are the most resistant minerals to weathering processes at the Earth's surface. Like uncemented sand, sandstone may be any color due to impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Since sandstone beds often form highly visible cliffs and other topographic features, certain colors of sandstone have been strongly identified with certain regions.

The best example of the architecture made by sandstone is The Red Fort Complex in Delhi, India, it was built as the palace fort of Shahjahanabad – the new capital of the fifth Mughal Emperor of India, Shah Jahan. Named for its massive enclosing walls of red sandstone, it is adjacent to an older fort, the Salimgarh, built by Islam Shah Suri in 1546, with which it forms the Red Fort Complex. It is a fusion of traditions: Islamic, Persian, Timurid, and Hindu.

Reference by Wikipedia & UNESCO