I have just realised (or perhaps I've put this on the Queen Victoria thread and completely forgotten about it)
Spiegl W. in Farbige Gläser has a description of what Topas-glas was:
Source -
http://www.glas-forschung.info/pageone/pdf/farbglas.pdfpage 30. Chapter heading 'Rosa Rubin und Topas-glas'
He begins the chapter with a long description of gold ruby glass.
BTW - note to Cagney, Spiegl notes specifically that the Harrach pink glass was
lead free (so I'm not sure whether other of their glass was lead glass or if I'm completely mistaken on that point):
'...The Harrach "pink glass", a pound of which cost 2 guilders 40 kreuzers to produce and was thus only slightly more expensive than the "special blue for overlay", as well as the "pink ruby according to M. E. Schmid"[6], were lead-free chalk glasses with gold dissolution. For a while...'
Then in the next paragraph goes on to say (google translated)
'Related to the gold ruby is the "topaz glass," which could be produced in Neuwelt as early as 1829 and by Lötz and Schmidt in the Goldbrunn glassworks from around 1830. In addition to the gold dissolution, a small amount of antimony oxide was added to the melt, which gave the glass a reddish-yellow color.''Mit dem Goldrubin verwandt ist das »Topasglas«, das man in Neuwelt schon 1829
herstellen konnte und bei Lötz und Schmidt in der Goldbrunnhütte etwa seit 1830.
Neben der Goldauflösung wurde der Schmelze eine kleine Menge Antimonoxid
beigegeben, das dem Glas eine rötlich gelbe Färbung verleiht.'Sooooo, when contemporary reports talk of 'gold-topaz' glass, is it referring
not to the colour gold but to the
inclusion of gold in the melt in order to make the colour topaz?
He described topaz-glas as being a reddish yellow colour. The Queen Victoria bowls are transparent yellow uranium glass colour not at all a reddish yellow colour.