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 consists of silicon dioxide (Silica) that forms rock. Obsidian is not crystalline and therefore not a mineral. Obsidian forms from volcanic lava that has cooled to quickly for crystals to form. Obsidian is termed a natural volcanic glass and iron and magnesium impurities produce a black or dark green Obsidian. The presence of microscopic bubble patterns cause Obsidian to colour sheen.