I'd heard so much about the quality of Burmese Rubies that I had to find out for myself. But I was in Bangkok, Thailand, home of the largest Jewelry Store in the World (so they claim).
I was politely informed that Thai Rubies were better in color and quality. Not being an expert, who was I to disagree. For me, they look great wherever they come from. Their website, however, does seem to acknowledge that Burmese Rubies are superior.
"The most valuable rubies come from Myanmar (formerly Burma), but they are mined throughout Southeast Asia. Good quality stones come from Thailand, Sri Lanka, and Vietnam. Kenya and Tanzania also are becoming more important as mining sources for ruby. But while the color of the stones from East Africa rivals the world's best rubies, most of these stones are fraught with inclusions that diminish their transparency and value. However, the East African stones are displayed to full advantage in cabochon cuts and have done well in the mass jewelry market. Meanwhile, Afghanistan, Pakistan and Russia have all produced occasional top-quality rubies, but the rough terrain in these areas has made mining difficult."
http://www.gems-gallery.com/home/