Hi and yes your vases are indeed a registered Davidson pattern, however the moulds for these vases were sold on/passed on and they cannopt be attributed to any known maker, but they are most deffinately flint glass that has been then SANDBLASTED and not acid etched. Acid etching is by far a more expensive and labour intensiveb method to achieve the effect, sandblasting is both quicker and more productive. Even to this day. I have seen these vases in three sizes. 25cms being the tallest. Each and every one of them from Davidson moulds/designes, but Davidson do not produce them in green and neither did they frost them. This does not detract, for you have a fine pair! Satin Glass they are not, but then again this does not detract. Their bases could be the give away to their place of origin and so study them closely. If there is any indications of "unfrosted glass" to AND throughout the bases, then they are are continental. Also, they are most certainly English if the bases of your vases are not flat! In other words, if the base of the pair is flat to the ground and without an interior, then they are more probably or not German. They are however, produced from Davidon moulds. Hope that helps? One other guideline, is to obeserve if any side moulding lines are present? These were apparant in all of the Davidon vases of this type. They were all polished out (in the main) even the those in cloud glass etc., and sandblasting will also discard any such moulding marks, but to less effect. Look INSIDE your vases for any moulding lines also. For sandblasting OR glass polishing cannot disguise these! They sure look super! Frosted 'N all!