Tourmaline. What a wonderful gem. It occurs naturally in many colors including a vibrant chrome green, blue, teal, bright pink, various shades of red, and grass green.
It is excellent for use in rings or pendants, earrings, and most anything else you can imagine. Best of all it is very reasonably priced even in stones weighing several carats. It is found in naturally worldwide with some of the best material from here in the United States–literally from coast to coast. That is Maine and California (and numerous places in between) produce tourmaline that is excellent for faceting.
So if you are interested in buying an affordable gem that looks and wears well consider Tourmaline. You will not be disappointed.