What is the formula for the area for a diamond?

Answer 1

Area assumes a flat plane. If you simply want to calculate the area of a diamond shape, you can follow the link, below to find the formula. It's a double triangle, correct?

Otherwise, if you're asking about the area of a gemstone, read on.

There are usually at least 57 flat planes -- facets -- on a cut diamond (fewer on a raw stone, but those shapes lack true straight lines).

Here's a link to the formulas for the different shapes you'll find on a cut diamond. You can decide how large the shapes are before you calculate the area.