Greg Merkel a Research Fellow at Corning, Inc. and a speaker on Iridescent Glassware at our Symposium responds to the comments on Tyrian.
Although I hesitate to weigh in on these things, my guess (and it is only a guess) is that Tiffany Blue (and I find it hard to imagine that this term was ever used publicly or else Tiffany truly WOULD have had grounds for his lawsuit) may refer to the vases (and occasional lamp shade) made by casing a cobalt blue glass over an opal glass, decorating with Aurene vines and leaves and, usually, possessing a Gold Aurene collar with a deep blue and white Intarsia zig-zag design. Shapes appear to have spanned the same ones used for Tyrian. However, as Beth has noted, Tyrian ranges from a pea green or sea-green to anything from a muddy gray to a bluish or purplish gray (within a piece or from piece to piece). The decorated blue pieces mentioned above are uniformly cobalt blue (thereby clearly distinguishing them from Tyrian). Also, the blue glass does not contain any silver, and therefore (although iridized), lacks the luster of Blue Aurene. Also, Blue Aurene (to my limited knowledge) is not found in these shapes with these decorations. In any case, if it is at a yard sale, buy now and research later!

An auction item for the Symposium is the following book. Some background is that there was a special engraved modern piece that was presented to the people of Canada from the people of the United States. This book describes the making. HTTP://www.civilization.ca/cmc/exhibitions/tresors/treasure/173eng.shtml