Aquamarine or Blue Topaz Stone ? (Jewelry Question)

is the chain and finding white gold, platinum, silver, or something else?

Its kinda blue blue for aquamarine , topaz maybe, but there may be several others . How bout blue tourmaline ?
Is the color much darker when viewed through the side v strait down the cut face?

we could tell with a gemmologists scope. Wed compre the index of refraction to a table of given Indices/

I agree that the color is too intense for an aquamarine. I would have guessed blue topaz. But farmerman know more about these things than I do.