Where can radium be found?

Could you elaborate on the question, "Where can radium be found?" I'm particularly interested in understanding the various natural sources and potential locations where this element might be discovered. Could you detail some of the geological formations or environments where radium is most commonly encountered? Additionally, are there any specific mining techniques or industries that are known to extract radium from the earth? I'm also curious if there are any other non-natural sources where radium may be produced or found in modern society. Please provide a concise yet comprehensive description of the locations and means of discovery for this intriguing element.