How to determine metal type on a President bracelet link?

[TheMailMan]

Greetings everyone.

I have a 16mm Rolex President link which I’m currently trying to determine whether is white gold or platinum

It appears to be from 1990s’ish generation, for example from a 18239 or 18206.

Weight is 2.1 grams without the screw

Width is 16 mm

Center link width is 7.8 mm

I was hoping that maybe someone here had either a similar white gold or platinum link and could help me out with the weight and measurements of their link to compare

Any other suggestion about how to determine the metal without ruining the link is also much appreciated of course.