Celestite, which is also known as Celestine, is occasionally found in highly compressed masses that resemble Angel wings – these specimens are referred to as Angelite. Regardless of it’s name, it is a Strontium Sulfate, and in its purest form it is crystal clear; although the most well known color is a soft baby blue. The blue may be caused by the natural irradiation of gold into the mineral. But it is also found in white, gray or a greenish blue color; the presence of Barium will turn it a brown, orange or yellow color.
Darker blue celestite is generally found to be more expensive than the pale blue variety, regardless of availability. Celestite is a mineral in it’s own right and is often confused with quartz.
Due to the fact that the sites where blue celestite is found, have almost been exhausted, rock crystal is vapor-blasted with gold and offered as a gemstone named Aqua Aura. The effect and sparkle are similar to that of celestite but not quite as strong.