#They fucking fool you man. Tuffs are like wizards in their own right. They shouldn't be allowed on the streets without a license.

[iamthepulta]

If it makes you feel better, that's an extremely normal reaction! It peels back the sort of half-truths that we're obligated to tell people in undergrad classes/grade school because they're already overwhelmed by classifying rocks via color and context.

Igneous, Sedimentary, Metamorphic are the boxes that we put rocks in because they describe the kind of environment we're looking for. And then the first level beneath that is, (for ign.) how large are the crystals and what color is the rock; (for sed) what are the parts of the rock made of, and (for meta.) what texture is the rock?

Those classifications are more that enough to overwhelm a beginner because each answer to the question corresponds with a physical environment of the earth. You have ~roughly~ six igneous rocks to correlate, five sedimentary rocks (+/- 2 depending on how mean the teacher wants to be), and six metamorphic rocks, (also +/- 2 depending on educational cruelty).

Geology is, for this reason, the most philosophical science, because there are 'rules' to follow, in the sense that technically if you have over 90% quartz in an igneous rock, you're supposed to call it a Quartzolite. But unless you sit and count out every single fucking crystal in an 1x1 inch representative rock sample (which some people DO and I applaud them for), you don't know that it's over 90% quartz. Or a sedimentary rock might change intermittently over several meters from a sandstone to a cobblestone because it had channels running through it. What do you call the rock then? A sandstone? or a cobblestone?

It'd be sadistic to make people just introduced to the concept of time over place and "sandstones can indicate a river or a desert environment, while cobblestones can mean a river or rockfall environment" to- "you could kind of name this anything sandstoney-sedimentary; the presumed interpretation doesn't change, but add these descriptors to make sure the people who come after you know you saw these cobblestones and weren't ignoring them; or it'll chaos at the conference bar because one guy saw some angle on the cobblestones here and you didn't."

Alternatively: "The Masters Student who comes after you will be EXTREMELY happy you said the word "anoxic" about this grey stuff because it correlates to their interpretation about rocks halfway across the world which have to be correlated to what this part of the world was doing at the time."

Do geologists just know all the rocks the same one would expect a wizard to know all the spells?