There are definitely people in the UK to study with but I don't have a list.
I suggest reading this article for an understanding of what the "crystal" (glass) bowls are.
As far as guidelines for how often to use them, there really isn't any.... but in general it's good to cultivate self-awareness around what it may be doing to you, if anything - including potential hearing damage. They are sound generators, not magic.... no special "energy manipulation" powers, or "special frequency" stories, but like anything, they can certainly be overused.
Sound Medicine Expansive Weekend Retreat!!
at the Omega Institute - Coming again September 25 -27, 2020!!
Please consider joining us!!!
For description and registration info: