There is a place in @Downtown called Sultan. He sells them. But if you ask anyone in downtown; everyone knows about it and they will direct you to the place
crystals as in gemstones? if yes then :@Downtown in most of the jewellery stores, you can find them at @Over The Rainbow but i'm not sure if they're open rn since it's considered a yoga studio, there's also a store, it's in a small alley right next to the @Istiklal Library Co. in swefieh, but i honestly don't remember the name.