These few black glass buttons are also new to my collection. Two have gold lustre and one silver lustre. The small one at bottom left has a copper lustre and the one on the right has a “diamond” in the centre. They were in a tin of buttons I went through a couple of weeks ago and I have cut cards for them but haven’t attached them yet. Apart from the copper lustre one which has a metal four way box shank the rest have self shanks.