Large Yellow Clematis Flower Moorcroft Vase

I have a large yellow Moorcroft vase with the clematis pattern in pink and purple.. It is made in England and has the Moorcroft stamp as well as a small 'w' on the base of the vase as seen in picture. It has no cracks, chips or repairs. I would be very grateful if anybody was able to provide any further information and a possible estimated valuation. Thanks!  

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