Red Sandstone Statue

The Old Red Sandstone describes a suite of sedimentary rocks deposited in a variety of environments during the Devonian but extending back into the late Silurian and on into the earliest part of the Carboniferous.Over time, the small quantities of iron-rich minerals in the sand break down and the iron is oxidized into hematite crystals (Fe2O3) that form as very thin paint-like coating on the quartz sand grains. The hematite crystals absorb all light colors except red which they reflect, giving the sandstones their red color.