Victorian twinkle buttons, that have a reflective inner layer that is meant to provide additional shine & brilliance; unused on their original cards.
I vended at the Cupertino Cherry Blossom festival in April. There was a lady there who was telling her friend that there was no way that the buttons I use were Victorian. Pardon? The colors were too bright she said. Yes, well that's because I try to purchase as many unused cards of buttons as I can afford. Just because the photos from that era are black & white, doesn't mean that their clothing was too.
Getting a full card of buttons is always a thrill. Even a partial card of buttons is a great find. However, the cards they come on are not always such a treat. In fact, 100+ year-old cardboard that's been exposed to too many elements can be down right disgusting. Like in the top picture, some are rusty, moldy, or crumble at the slightest touch. Others will surprise & delight as much as the buttons with their charming artwork.