Insert above the background now such a texture.

Snow Queen photo effect in adobe photoshop cs

Copy this layer now and turn around the copy, applying Edit – Transform – Flip Vertical. Merge both these layers and change the color (Hue/Saturation)

Snow Queen photo effect in adobe photoshop cs

Open now a picture representing the brooch.

Snow Queen photo effect in adobe photoshop cs

Place it on a layer under the girl's one. Mark it out and erase the background which it was situated
on and then decolorize the layer.

Snow Queen photo effect in adobe photoshop cs

Make the brooch look bluer, applying Image – Adjustments – Photo Filter.

Snow Queen photo effect in adobe photoshop cs

Get back to the background's layer and work with the color: make it profounder: (Curves)

Snow Queen photo effect in adobe photoshop cs

Insert on a new layer the picture of a diamond.

Snow Queen photo effect in adobe photoshop cs