HD not mounting, reading in diskutility, not erasing, not allowing eject etc. HELP!

I recently had an absolute nightmare where I was streaming over my network from my MBP 2012 to my ATV 3, simply playing videos from my itunes playlist.

It then all of a sudden cut out, and I tried switching my mac back on but it kept dying after the boot logo. So I tried dumping PRAM, booting into recovery etc. It was then I notice that the HD (my 320gb Hitachi HDD which came with the mac originally) was displayed as connected but the one and only partition was displaying as unmounted, and would allow me to erase it, nor would it allow me to do anything. I attempted verifying (which came back as OK) and repair (which was the same) both of these I've repeated countless times.

Also I tried disconnecting the HD and then putting it all back together but this made absolutely no difference.

Either way I used this as an excuse to upgrade to an SSD, which is running fine and is now running mavericks etc.

The problem I'm having is that I want to transfer some of my old data (i.e. films, and 4 years worth of art work) onto my SSD, erase the old HDD and use it as a portable backup as it's now in a caddy. However I'm unable to access any files, it's displaying exactly the same as when it was originally inside my mac.

I've included a screen shot of the Disc Utility screen and a couple of the error messages I'm recieving.


I'm beginning to give up hope that I'll be able to access my files which is a bit heartbreaking, most of it is backed up online in some way or another so it's not the end of the world, however I'd really like to use the HDD, it spins perfectly, no clicks, no issues at all, and as you can see from the images it's being read.

Any help/ideas would be really appreciated.

 

Hey thanks for the quick reply.

I only tried erasing when I really have up hope (with only having 64gb of storage on the SSD I was going to make partitions for time machine, and use it as a storage device).

I'll download disc warrior and try booting up Linux (though I don't have a partition for it, nor do I have access to a Linux computer)

I'll get on disc warrior now though.

 

Yeah I've just hit that stumble. I'll try finding a download for linux and make an attempt at using it now.

----------

I'm currently attempting to use a freeware equivalent to disk warrior called Disk Drill, it's again recognised the drive, but is not able to rebuild it, I'm running through the long process of attempting all the recovery methods.

 

Right, I've managed to finally get the HDD to locate files using disk drill (which is now asking me to pay £50 to upgrade to the pro)

I'm assuming my best course of action to format the drive so I can recylce it as a back up will be to do that through linux right?

 

I just tried force mounting in terminal (since I've got a big download on the Linux file, and it registered as 'permission denied'.

I give up.