How to detect SSD in Mac OS X?

Question

Is there a reliable, quick, deterministic way (i.e. not a benchmark) to check whether the system drive Mac OS X is on is a Solid State Drive?

Is there any other

Answer 1

This only seems possible for internal drives. I could not find a way using IOKit to query a Samsung T5 external USB 3 SSD for its SSD-ness (nor a Toshiba Canvio USB HDDD). I did manage for the internal drive in my MBP, though.

Disk utility also doesn’t think the Samsung is an SSD, so that makes me think there may not be a way, other than to measure actual performance.