Based on your description, your vase sounds like cased French opaline. while opalines were made elsewhere, the decoration you describe sounds more of the type done by the French. These vases began to be produced around 1880 and continued into the twentieth century. It would be impossible to guess at the age without seeing the vase. Your vase was definitely not made in Bristol.
Hope this helps a little. Edie Crawford SO RARE! GALLERIES
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