Is Obsidian Intrusive or Extrusive?

Answer

Obsidian is considered to be a black extrusive, igneous rock. It is characterised by a shiny surface and it is created by volcanic gas. Obsidian comprises of high contents of silica.
Q&A Related to "Is Obsidian Intrusive or Extrusive?"
intrusion - intrusion is when magma cools down inside Earth. extrusion - extrusion is when lava cools down on Earth.
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Obsidian is an extrusive rock rather than intrusive. Extrusive rocks are formed by
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Intrusions are magmas that intrude into a preexisting rock. Extrusion are lavas that extrude onto the surface of a preexisting rock (i.e. the surface of the Earth, whether it is on
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Extrusive formations flow out of the Earth onto the surface of the planet, such as the basalt deposits of South America. Intrusive formations occur when magma does not break through
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