Odds of Getting In
Your odds are good if you've graduated from a training program or trade school. People are retiring left and right in this field, and if you're ready to start right up without any need for training, the jewelry shops are going to snatch you up—you irresistible thing, you.
And when you have more certifiable skills, it's less likely you'll be replaced by a computer in the coming years. That's right; technology has reared its ugly head in the jewelry design industry, and half the work seems to be done by computers now (source).
If you want to work for yourself (careful—we've heard you're a tough boss), competition will be intense. It's going to be difficult to establish yourself and get a business started. Really, really hard. Best of luck.