Resolved Help Needed - Formatting my LaCie hard drive and it has become stuck in the 'Partitioning' phase.

[Sideshow Mel]

I'm very new to MacRumors and forums in general for that matter so bare with me. The memory on my Mid 2011 iMac is getting close to the limit and so I've turned to using external hard drives to store my footage. When I came to transfer some video across this morning I was surprised to find my LaCie Rugged 500GB did not establish a connection via FireWire. I restarted my iMac (the good old 'off and on') and was met with an error message that read something along the lines of "The external device you connected is not supported by your computer". I wouldn't say this hard drive is 100% operational by any means as it approaches 4 years old and has been sent back to LaCie once before but it came back in a working condition and I have used it on the same Mac, and others, since.
It was showing up in disk utility so I tried to format it (Mac OS Extended (Journaled)) hoping to solve the issue and it raced through the first half of the progress bar but has become stuck. It has stopped at the 'Partitioning' phase (as pictured) and the estimated time has incrementally increase ever since starting at 'less than one minute' and as I post this it is currently on 34 minutes. Any ideas/solutions? Can I unplug the hard drive mid-format or is that a sure fire route to corruption?

 

[Sideshow Mel]

The estimated time reached 1 hr 30mins, I cut my losses at that point and diconnected the hard drive. Reconnected via USB and was able to perform a successful format. Now the drive works through both peripherals. Case closed.