The best way to test an unknown HDD or mass storage medium is with HDCK.
Version: GIT Web: https://github.com/tomato42/hdck
Nobody likes losing precious information due to a hard drive failure, and that’s why we have backups and SMART-capable hard drives. Still, it’s always good to have extra diagnostic tools that can warn you about possible upcoming drive failure before it is too late. One such tool is HDCK (Hard Drive Check). This one is much newer than Smartctl (which you might already know), but has still existed for over a decade. Fortunately the HDCK code is updated and well-maintained, and the software remains useful.