[ALUG] SD card recovery

I'm still waiting for delivery of a pre-installed SD card and card reader from The PiHut for my Raspberry Pi so, fed up waiting, I bought another card reader from Anglian Internet in Norwich. I can now see a 16GB card from my digital camera, but the machine still won't see the other two 8GB cards which I used for a previous attempt at writing images. Are they toast or can I recover them in order to write images to them?