Old buttons like that can be very valuable. As a metal detectorist,, many of my friends love finding old buttons. I've never actively searched for any,, nor found some,, but I have seen several.
Look on the back. Sometimes there is stuff there too.
And buttons can look very similar to others,, but be different enough to make a big difference in values.
Yes,, some types are much more common,, but before discarding it or thinking it's "nothing" do some serious research,, and get better pics of it.
Plus,, there are books & lots of online info about them.
We had a guy in our club find a larger odd button long ago. He didn't think much of it,, and it was in his "junk finds" box for 12 years. Then he discovered a reference to something else,, that made him look at it again. Turns out it was quite valuable,, & he sold it for $3000.00. And that was about 20 years ago.