Granite (0 transparency) bottom
Foil (0.6 transparency) top
I’m leaning towards the top picture because metal isn’t often a material associated with water, and it’s a bit brighter. If you think I could improve on them both please leave some recommendations. Comment which you think is better and why.
I would choose water depending on how the map looks. But based on the two images, I would prefer the first one in most cases. It’s not too bright nor too dark. There are also unappealing stripes in the second image, which I cannot notice in the first image.