Hi Tom, I wouldn't dismiss your vase as a reproduction immediately, it certainly deserves further investigation at the very least. Personally, I couldn't tell you if your cameo vase was a Galle reproduction or not, however, I'm sure someone will advise you in due course. Possibly the weight may not be the best indicator to judge its authenticity.
Just to mention there is no shortage of Galle tip (reproductions) along with other Cameo makes currently being reproduced in eastern Europe. This is an area that can be a minefield, if you search online under Galle tip vases you will find hundreds of examples. Some are clearly marked 'tip', however, many are also not marked in this way. This said I wouldn't discount your vase until you have a definitive answer, as an original would be a very nice find indeed. Hope this helps a little, sorry I couldn't give you any other pointers.
