Hi Vince,
You've got the stones nice and sharp but the image is lacking overall interest. It's all a bit tight and central.
I would suggest position the stones in a similar manner (maybe with the larger red stone at the bottom). Take a lamp and maybe place it off to one side so as to create similar shadows as to what you're seeing. Adjust the lamp to create longer shadows (such as seen during later evening before sundown). A soft light bulb would be good especially where glass is concerned.
Then maybe frame the shot so as to allow more space around the stones so that they're to one side of the image. Maybe even select 3 stones all of the same type, spray them with water to get some droplets etc. on?