You don't need more light, you need more balance. Place the photo area next to a window with the curtain/blinds out of the way. You need white on the other side away from the window. When the light comes in, it will bounce off the white to help eliminate shadows. Right next to the window, you need something to diffuse the light. The idea is to create light as uniform as possible. You also have a reflection in the gold cap which can be helped using a black background so that the reflection is stopped. You also need to focus on the actual image you're taking a picture of so that the background blurs a bit. These videos will show you how.