Cairngorm, (also called Scottish topaz or smoky quartz), a smoky, yellow-brown variety of quartz. It is named for the Cairngorm Mountains of Scotland. The stone is highly prized in Scotland and is used for various ornamental purposes. Its value depends on transparency and shading. The mineral has been found in Great Britain, Siberia, Spain, and Switzerland, and near Pikes Peak, Colorado.
Archaeology is the study of humanity's material remains -- even a piece of an ancient pot can tell us a lot about the past. But how do archaeologists make sense of these relics?
When it comes to fossils, specimens like Sue the Tyrannosaurus rex grab much of the attention. And while Sue is a staggering 67 million years old, she's a new kid on the block, compared to some of the oldest fossils ever found. What's older than Sue?