Usually the lava flows come towards the end of the eruption, once the magma has lost enough of its volatiles to flow more quietly. Cinder cone eruptions are comparatively short lived, and thus cinder cones are much smaller features than stratovolcanoes and shield volcanoes (usually no more than a mile at the base).
<span>The mineral crystals in obsidian are too small to see without a microscope. This is because the rock cools so rapidly from magma that crystals barely have time to form. Obsidian is a normally happening volcanic glass framed as an extrusive molten shake. It is delivered when felsic magma expelled from a well of lava cools quickly with negligible precious stone development.</span>
A law is something that can be measured or observed to be true. A theory, is something that can be assumed to be true based on the best available knowledge.
