Thanks, and yeah... I missed that thing about color count and added a little glow effect to make it look more interesting , can remove it without a problem) 

That's bacause of glow effect on gem, and some details in backgournd. I'll fix this )

Anyway thank you for advice about that, and also, I liked your version of colors on the grass very much!  

You have 2054 colors here, which means there's some kind of NPA effect, like a gradient, semi-transparent layers, etc. You should take a look at the background and see if you can clean it up a bit, otherwise this won't be accepted in the gallery, I think.

Here's an edit for you. About 60 colors, could easily be reduced further. Also changed some colours, because the dirt and grass looks like it belongs equally well under a sunny, blue sky.

I love the ground and grass texture on this and nice subtle mist. Unfortunately the glow around the gem needs to be removed and something else pixelled in to replace it since it is a filter tool in order to be accepted