How do I see a SD card in my USB reader plugged into USB

I have a SD card I need to see on my desktop, but it doesn't show. I see it in Disks. So I know it is there. I clicked off the check box in Mate Tweak for drive.

Is it showing mounted or unmounted in Disks? If unmounted did you try mounting it?

I am also having the exact same issue as Sparks, any SD card I put into my reader shows up in Disks but nowhere else. And the option to mount is greyed out. Only options are format, create, restore, or benchmark partition/disk.

Did you try opening caja or disks as sudo (root)? Otherwise I am not familiar with raspberry pi

My apologies, I didn't notice this was an RPi question. I had the same question and didn't want to make an identical post, none the less opening caja/disks as root didn't work.

Does Disks show any partitions on the SD card? Furthermore, does it say what size the SD card is anywhere (for example, "8 GB Volume")?

If not, the SD card reader may be somewhat defective. Is this an internal card reader on a laptop or desktop system, or is it an external USB-connected unit? (I know @Sparks titled this topic so that I didn't have to ask this question, but I can't know for sure whether you have the exact same problem as @Sparks.) Try removing and re-inserting the card several times, brushing the contacts of the SD card off with a soft, clean cloth each time before you re-insert the card; mechanical contact issues are common with SD cards.