Used specifically in geology; avoid in non-scientific contexts unless metaphorically.

Geology Context

Igneous implies natural formation, not crafted by humans.

Not Man-Made

Igneous rocks primarily make up Earth's outer shell, useful in geography.

Earth's Crust

 if they in defense of their their nest then your finance will kind of come in and try and defend in a big grouping but and then not really they just kind of go in lines and they'll go and find food and they distribute art but they don't actually swarm anything unless it's either food-related or in defense of the igneous that they are close to so it's a

Safari Live - Day 125 PIPE...

 Now of course, you can only make a fossil in a sedimentary rock, a rock made by sand and mud. You can't have a fossil in an igneous rock formed by magma, like a granite, or in a metamorphic rock that's been heated and squeezed. And you have to get yourself in a desert.

Hunting for dinosaurs...

 it crystallizes to form young, hot igneous rocks. The heat from these rocks drives groundwater towards the surface. As the water cools, ions precipitate out as mineral crystals, including quartz crystals from silicon and oxygen,