I am typing out a section from the book 19th century glass by albert revi, that quotes a trade journal "london, august 29th 1878 the followign commentary By Her Majesty Queen Victoria, with the specific reference to Thos. Webb and sons "bronze glass" appeared
"we noticed a fine selection of the new bronze glass, discovered and made by Messrs. Thomas Webb and sons, of stourbridge. Its purple bronze surface shines with the hues of the rainbow, such as they appear on molten lead, or on pieces of steel which have been tempered in gradually diminishing degrees of heat, in fact, the appearance of these jars, vases and bowls is such as of they had been made of oxidized steel or copper and their remarkable weight and solidity makes us believe that some metallic preparation is used for coating or impregnating the surface. The Shapes are in preference borrowed from Dr. Schliemann's finds at troy and Mycenae, owl-faced and curiously-lipped vessels predominating. Although the specimens we have seen combine the character of curious adn ornament, the manufacture might apply their process with equally good effect to vessels which in shape belong to more advanced periods of greek and roman culture, and therewith meet the taste of the refined public. Like the iridescent glass, an invention of the same firm, bronze glass will find admirers, and be utilized in many ways for the purpose of ornament. It has already attracted considerable attention at the paris exhibition (1878), likewise at Grosvenor Gallery, where Mr. Goode placed some of his finest specimens"
but then revi goes on to say that it was a mirror like sheen not a fine velvety sheen. I'd call this one velvety. France was also big into the iridescent glass. They say in Bohemia lobemeyer was the leading exporter of iridescent glass. I just went over to look at it again, it is shiny and not velvety when looked at straight on but when looked at an angle and in light you can see velvety as I captured in the pics. So having not seen enough examples of both kinds I am not sure how you'd count this.