Wanna ask you Pleas give me an answer

yes today i get a u70 black(lol) from a mystery item

Yes but low chance i got u70 purple and red from itthe rare,blue or yellow mystery capsules dont give stones only the normal white ones

i got 4x u65 red und 6x u65 blue from mystery items for a few weeks

Exact same chance to find a regular stone.

Every single item that drops from a mob has a 10% chance to be turned into a "?" needing appraisal. if said "?" happened to be a stone you wouldn't know until you've appraised it. So far i've found a few u60 and 1 u70 stones from them.

You can, it's the same likeliness of dropping one though (4/???)
The ??? Stands for how many materials a mob can drop... I would expect something around 10000 or more, since they can drop a jacket, and every jacket has A LOAD of possible variations for effects and such!

In DBOG, I got:
1 U65 Purple
1 U65 Red
1 U70 Blue
2 U55 Red

i got a lots of red ans blues stones from mistery items. Just pick up every one