>>2189947Marcasite depends on location but mostly sedimentary rocks or coal beds can have em. Check out mindat and scroll all the way down for a worldmap with logged sightings.
For pyrite depending if you want a big nice cube shaped one id suggest searching along old traintracks as the granite used there can have some decent specimen. Or just bite the bullet go on mindat and search for old mines with all kind of ores. Pyrite isnt hard to find at all.
>>2190209you only see "common" rocks because the minerals didnt have either the right time/pressure/chemical enviroment to reach a decent size because the earth isnt a stable system and those things need a pretty long time to or the right enviroment to grow to a decent size. If you take a magnifying glass you should be able to notice and tell apart some minerals maybe by colour or shape or just by their refelction of light. Its fun to get into anon but wear your saftey glasses while smashing and Glück auf!
