This I think is a taffeta sharkskin fabric - I'm not sure of the exact vintage or fiber content. It's lovely and heavy, with a slight stretch from the weave (not a spandex stretch fabric). Color is a steely grey or dull silver, with a subtle sheen.
This is a 3 yard length of 58" wide fabric, enough for evening trousers or a shirt, or a little (not quite black) dress. Very nice!