The geometric lines and triangular shape of this small collection ensure these buttons are primarily from the 1940's or 1950's. Separated from the rest of the coffee can button collection my grandmother saved for years, they have been chosen because of their shape and style. The three matching dark brown triangular ones are probably 1950 coat buttons. They are 1-1/4 inch with one of them marred on one edge by a scrape (can be seen in photos).
The matching pair with the space age circular design are clear, but with an olive green cast. Both have shanks for sewing. They are 1-inch. The brown one with a square shape on a round button is 1-3/8 inches. Black one with concentric circles measures 1-7/8 inches and very thin. But the dark brown one with angular lines in four quarters is even thinner - wafer thin, in fact. It measures 1-3/8 inches. All of them failed the 409 Bakelite, but are now cleaner for that experience. Don’t hesitate to ask detailed questions.
To see more buttons in this shop, make sure Dotty Lee's Treasures shows in the top right corner of this page. To the right "What are you looking for" type in Buttons to see the whole collection. Buttons can be combined to save shipping cost.