Now I need to post a shiny that was actually brought back from the field. My friend Sachi found this in Iceland, and as far as I understand it she took herself right to a glacier bed and systematically cracked open every rock until one of them yielded treasure. The most amazing thing, though, is that she gave it to me! Because (unlike some of us, I’m not naming names) she’s a superior human being, capable of parting with her finest shiny for the sake of friendship.
marianchurchland.com 
I strongly suspect this is the petrified dragon egg.
It would hatch the tiniest dragon ever, but that doesn’t mean you’re wrong.
Whoooaa cool~ Do you have any idea what that mineral(??) is inside?
It’s probably quartz/rock crystal. But since I’m not an expert and can’t be certain, I feel like that leaves me an avenue of possiblity: it could be something weird and rare that just looks like quartz!
Ok then, headcanon: a fossilized ancient unicorn tear. Very powerful if you can figure out how to unlock it’s magic! :o
This is why I gave it to you. So the shiny would become a famous shiny.
Don’t be fooled by the rocks that it’s got, it’s still it’s still shiny from the block…