The mineral crystals in obsidian are too small to see without a microscope because it cooled very quickly. This rapid cooling occurs when molten lava reaches the surface, preventing the crystals from growing large enough to be visible to the naked eye.
The mineral crystals in obsidian are too small to see without a microscope. This is because it _____.
formed below the crust
cooled very quickly
formed at high temperatures
cooled very slowly
1 answer
1 answer