Plastic bangles

After a week away at work I got the chance to go hunting!
Just so I get this right as I’m never sure about plastic!- the stack of 7 all have a seam and all have wear on them so more modern and nothing special?
The salmon pink one has no seams and pretty much no wear on it- same colour as a celluloid necklace I have but quite heavy- celluloid? Bakelite?.
The white and brown swirly one has no seams and no wear- no idea about this one?. All from the same seller tied in a bundle not that that necessarily means anything.
Any info or good guesses would be great Thankyou

 

You know it's an interesting thing, does anyone know the difference between lucite, bakelite, plastic and celluloid! Bakelite smell I hear but have none. It really is about holding it in your hand and feeling the quality but photos-very hard. The white one looks nice