Bracelet acai beaded bracelet

I found these today at the thrift store and I don't know what the beads are made of it seems like they are made from something natural because they are not uniform in size they all have a spot on them maybe some kind of bean or plastic made to look like a bean?

SOLVED by me they are acai beads are from the amazon... the bead is the inedible nut from the center of the berry

I drink acai berry juice all the time (it is considered a super food full of antioxidants) so this is very cool to find this!