Weird crust

Hello, My cat has developed these weird crusts on her jaw and it looks like a wound but it's been like this for a while. I saw that this could be because of the food bowls so I switched plastic ones for metallic ones but it doesn't go away. What could it be? She doesn't have any parasites and she isn't scratching it. It's just there.  

Hello!  There are lots of 'could bes', but likely only one or two are appropriate to your cat.  I have seen cancers present like this - cancers do not itch or bother the cat.   Much more commonly I have seen erosions, perhaps with some bacterial infection, yeast or demodex (deep hair follicle) mites or allergy involved.  The lesion might start as a scrape or chemical burn or scratch.   I would recommend showing it to your vet as they might either want to trial a treatment or to test it with a view to finding a diagnosis.  Food bowl reactions definitely happen, especially once skin has been damaged.  Wishing you all the best and please do let us know how you get on from here.

Ps I don't know how your cat is in herself, but just occasionally erosions can appear secondarily to underlying disease eg uraemia, or as a result of underlying infection (abscess) or trauma.  I think that a vet appointment may be good, especially if this is not clearing up very quickly.