While perusing the many drawers filled with buttons at Archangel Antiques a few weeks ago, I came across some lovely vintage specimens that I was told to be made from vegetable ivory. According to Wikipedia it is also known as corozo, a name used for the tagua nut found in the South American rain forest. I was very happy to read that both humanitarians and environmentalists appreciate its use.
I bought a few buttons that day, all of which I have already used to adorn several new handbags I made. Posted above is a lovely example you can find in my shop.