I have placed 200GB SanDisk card inside Nifty adapter and put it into SDXC slot in my Mac.
I want to use it as permanent & encrypted storage. Unfortunately encryption requires GUID partition which I tried to create but without any luck. "Partition" option - under "APPLE SD Card Reader Media" in Disk Utility - is greyed out.
P.S. I own Late 2013 Macbook Pro Retina 13" with MacOS Sierra (v10.12.6) installed.