Signed Art Glass Vase Cased Clear Confetti White Swirl Blue Crest Amethyst Pink

This is a mystery piece, signed art glass but I cannot make out the signature, it looks like Imbat above and Garth below the date but neither of those searches yielded any results. This is a clear cased glass piece, sort of a confetti swirl design on an opaque white background with a flared blue crest rim. The main colors are a clear amethyst - which fades to pink, pale blue, matching the rim and a green/aqua color interspersed with black. It has a rough pontil scar & engraved signature on the base. If you know the artist please feel free to pass that along to me. Size: 6" h x 3.75" w Condition: Excellent, I am not seeing any defects. Keats said "A thing of beauty is a joy forever". Each of us has a different idea of what "beauty" is. I find unique vintage items and offer them to you, the beholder. Have you found your thing of beauty?