Talking about the first 2, they look somewhat ready, not much to say on them.
The 3rd could use some more detail, it seems to be missing smoother shading. Oh and I thought emeralds were green

From the 4th on you only defined a shape and filled the parts with colors, sometimes using some gradient. Well looking at the first 2 items I think you could do much better with a bit of effort (supposing they were really made by you).