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 has been used to make arrow heads and blades, as well as ornaments for thousands of years by people such as the pre-Columbian Mesoamericans and the ancient Egyptians. In its pure form, obsidian has a dark body colour due to the presence of iron and magnesium.