Hi! I live close to the Thai-Burmese border and have dealt with rubies, sapphires and spinel. What I can tell about rough rubies is that the dealer knows what kind of carat yield a rough stone will bring a lot better than you do. So if you're buying low grade rough rubies, yes they will be really cheap. But if you're taking about top quality pigeon blood rubies from Mogok, forget about it, it's about 4000 per carat for stones above 3 carats. You have to know what you're doing, and you won't get an incredible margin on one stone and turn out a great profit unless you already have a very willing buyer or, you already have your sales channels set up. If you want to buy mid-range rubies (pinkish from Mong Shue for example), then yes, you can find great deals.