Quartzite, a metamorphic rock derived from sandstone. In some quartzite the sand grains are recemented with silica. In others the metamorphism (change) of the sandstone results from great pressure. Quartzite is extremely hard and highly resistant to chemicals. It has a glassy luster and may be white, gray, pink, or brown. Quartzite is used in making glass and to pave roads.
Chinook, the American name for a warm, dry wind that blows down a mountainside.
We hear about humidity in just about every weather report on the nightly news. There are several different ways meteorologists measure humidity, but relative humidity is the most common measurement. What is relative humidity, though? Find out in this