//You're studying jewelry design, and 'gemology' right? IS there reaLLY a "dragons-fire" opal? Or is that lab-created nonsense? It's like a deep fuchsia/magenta shade. (Sorry I just am not... a lab-created gem fan) it's like hydroponic tomatoes to me. Convenient, but it's not the same... :( I'm trying to find its source, and can't really. I figured maybe you would know?
I am indeed a Gemologist, not a jewelry designer. I had to google “Dragons-Fire” because I’ve never heard of it before, but it is absolutely not a real opal. After some further research I found that it is glass. Check out this incredibly detailed tumblr post from Chatsworth Vintage for more information (scroll down for dragons breath glass).
While dragons breath is super cool looking, you should check out the different types of natural opals, there are so many, and they are so cool! Look at this GIA page for some more info.
Just FYI - The best way to tell if an opal is real is to look at the bottom or sides to see if it is a doublet or triplet. These types of opal use just a thin layer of opal and other types of stones (such as quartz) to either 1. Trick you into paying for a full opal or 2. increase durability.
You can also use magnification to see if it has a subtle “snakeskin” pattern - not the color, but the actual surface of the stone. This means the stone has been lab created.