Haze on lens - is it fungus or something else?

[kubrick]

Hello there.
I would be grateful for any help that this form can provide with a little problem I have with a lens I bought from EBAY.
The rear element seems to have a uniform greyish haze on it, it doesn't look like pictures of fungus that I've seen on the Internet, it's far more uniform and far less spiderweb-like. I have tried cleaning but this does not work, as far as I can tell it is on the inside of the rear element. The lens is for a Mamiya TLR. When I compare the lens with the original lens which came with my camera, the original lens does not have this haze.

Can lens fungus ever appear in this uniform way? Thanks for your help.

[Marc Kurth]

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