To view all our multimeter ranges go to http://bit.ly/1EdnDeo. In this video, Josh shows us how to use a multimeter to check for faults in an electrical switch.1  Howto & Style. 2  Standard YouTube License.o view all our multimeter ranges go to http://bit.ly/1EdnDeo. In this video, Josh shows us how to use a multimeter to check for faults in an electrical switch. 1  Howto & Style. 2  Standard YouTube License.
Black is the most common color of obsidian. However, it can also be brown, tan, or green. Rarely, obsidian can be blue, red, orange, or yellow. The colors are thought to be caused mainly by trace elements or inclusions.
Obsidian was so named from its resemblance to a stone found in Ethiopia by Obsius. It was used in antiquity for amulets and necklaces. Obsidian is a naturally occurring volcanic glass. It is usually an opaque black or grey but may be yellow, red, greenish brown. Obsidian may have an iridescent sheen caused by inclusions. Obsidian is used for ornamental purposes and as a gemstone. Many colored glasses are sold as obsidian often claiming to be natural.