In order for me to properly assess what you have I will need to see a clear, in-focus close-up of the mark.
Please send the photos at your convenience. There is not an extra charge to provide more pictures here.
Your Belleek mark in black is referred to as the "Eighth Mark" which was first used in 1993.
Your fairly contemporary piece with pink lily decoration and country trellis design by the firm has a high sale value of $15 - $20 on today's market.
Here is a link for you to a match that sold for $14.99:
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