Help With ID On Silver Bowl

[polkadotplates]

Hello,

I purchased this at an estate sale but am at a loss for what it is used for.  Could it be a porringer? Also, help with the makers mark. The first mark looks like a C with AF inside, second mark is a castle, third mark not sure. Thank you in  advance for any help you can give me!

Polkadotplates

[sonomabarn67]

Can you read the close up photo of the marks? Neither can can we. They are incredibaly blurry (out of focus). Your form is a tastevin for sampling wine; may be silver or may be from a gift shop.