I think this is the most well known and critizied form of Divination, Crystallomancy aka Crystal gazing. Over recent years this form of Divination has been doubted and pushed aside, many think that crystal gazing/ reading a crystal ball is fake. Yes I agree that Hollywood or scam artists make Crystallomancy seem as if when the Diviner looks through a crystal ball he/she will see a puff of smoke and from it the future or the past, even the present shall be shown, yes I do agree that's a load of crap.
There is real truth in this art. Normal when the Diviner is looking through the ball, he/she is falling into a deep trance, preceving images much like when your water scrying or any form of scrying. This of course is a form of scrying just using crystals. Though it is believed if one can achieve perfect accurate readings from the crystal while in this hypnotic trance then their psychic energy is very acute. If you are interested in this, it's always best to keep your ball cleansed and charged, I'd reccomend using your own energy to recharge the crystal or let it soak in water then allow the sun's rays to dry it off. Crystals are very reflective, which increases the Diviners chance of going into a trance.
My method of doing this is while I'm in this "Trance" I'd grab my sketch book and sketch what I see, some times what I see can be vivid. So after I've done it a few times i'll compare each skectch and piece together everything, sort of like a puzzle.
Thank you, any comments please reply, I'd be happy to read.