So I’ve discovered that after formatting some SD Cards for use with some ARM based devices means that the card is left unformattable and unable to be read or reused. Whenever I went too format the card using Windows Disk Utiltity or Mac Disk Utility it would fail and tell me the media was not ready. Futher investigation let me to discovered that some of the images I was using start writing the image to the file at 8 or 16 bytes, leaving the 1st sector unformatted with the uboot image.
So I found on the SD card Association website a tool that formats SD Cards to make them useable again.
The link to the page is:
SD Card Formatter
SD Card Formatter For Windows
SD Card Formatter for Mac OS