It is a mitered edge. I am having one done in my bathroom in order to have a thick looking countertop on my vanity. My fabricator has fabricated many of these - he told me that I just need to let him know what size to make the mitered edge.

It will affect the height of your vanity - so, you need to plan ahead in order for the final height to be whatever you've determined. For example, I want the final height of my vanity (with countertop) to be 36" - I am having a custom vanity made in order to have the final result meet the height I've determined.

If your current vanity is the older 32" height, adding a thick miter like shown in your inspiration photo above should work out fine. However, if your current vanity = countertop = 36" - you'd have to somehow make some changes to your current vanity or your overall height will be too high.

Wry helpful to know, thank you!

That's a great look with the taller backsplash too. And what a way to update shorter bathroom vanities if you have them!

That is a very expensive custom marble creation from your local fabricator. Calcatta Marble has gotten to be one of the highest priced options available.