Iceberg Above and Below Water With Rainbow Sky

Create an image of an iceberg showing both the above and below water portions. The above-water part should be white and majestic, towering against a clear blue sky there are voluminous clouds with a rainbow and peek of sunshine.  Below the water, the iceberg should extend in a much larger mass, with varying shades of blue, indicating depth and density. The water should be crystal clear near the surface and gradually darken with depth.