Ingredients:
Aluminum Oxide - 1 handful
Chromium - a small amount
Iron (optional) - small pinch
Flux - 1 very large handful
Preheat electric oven to 1300 deg. C. (2340 deg. F.) In an ungreased solid Platinum crucible, mix together one handful Aluminum Oxide, a small amount of Chromium (double the amount for a pigeon blood red), and a pinch of Iron. Leave Iron out if you want a Burma Ruby. Stir in a very large handful of secret Flux material (made from eye of newt, toe of frog and hair of kitty), Place carefully in center of slowly cooling oven for about 3 months. NO PEEKING. Remove when oven temperature has reached approximately 1000 deg. C (1800 deg. F) and immediately pour off Flux. Remove crystals from crucible using a 2 lb. ball peen hammer. Send to Thailand for cutting before serving. Usually makes enough to pay for lights, heat, cat food and underpaid, but overworked employees.
We hope this explains what we use and how it's done.