"Verified" means the math engine is uncorrupted. When you input a critical angle (e.g., 41.2° for quartz), the verified version ensures that angle is written correctly into the .gem file.
In the context of software plugins, "Verified" may indicate that the file is a native output of the Gem Cut Studio software, ensuring it retains parametric data. This allows other designers to edit the stone's parameters (e.g., changing a 2mm stone to a 3mm stone) without remodeling it from scratch.