If the SD card says it is blank, then it was, more than likely, erased or formatted. That being the case you usually cannot get any data off of it. However, there are some applications and programs out there that can try and restore the data. You would have to install the program to a computer and plug the phone into a computer (with the SD card in it of course). Run the program and see if it can recover any data. I have to say it is a long shot, but can't hurt to try.
Side note... Many of the programs (most actually) are free to try, or claim they are free, however if they recover any data, they often require you pay for the program to actually access the data recovered. The good part is you don't pay unless something is found.
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