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 is mineral-like, but not a true mineral because as a glass it is not crystalline; in addition, its composition is too variable to be classified as a mineral. It is sometimes classified as a mineraloid. Though obsidian is usually dark in color similar to mafic rocks such as basalt, obsidian's composition is extremely felsic.