Jewellery what materials

Another one tonight no antiques but I'm learning a lot about jewellery and I hope it's ok if i post stuff thats not necessarily old but stuff i dont know about dont want to overstay and break any rules.
I was wondering what these are made of. The round thing is interesting is a timber inside and looks like mother of pearl with other materials and a filler of some sort looks well made imo about 70mm across not big enough for a bangle thought something for hair chris

 

I'm no expert, but some of the streaky stones on the necklace in the second picture look like agate to me (possible carnelian, too?). The necklace in the third pic looks like it's made out of shells. The bracelet looks like it's made possibly out of bone and polymer (or some other material) with bits of shells or stones. But again, I'm no expert.

 

Agate and carnelian on one, MOP and abalone on the other. Bracelet is MOP in resin, modern Indonesian.

 

From the one green bead shown in close up, guessing those are green aventurine, another member of the quartz family with carnelian & other chalcedonies.

 

I have the similar one to picture 2. Mine is agate

 

Yes, I can see one green aventurine bead. The others you mentioned as well.
The second one is white mop and abalone mop.
The bracelet a napkin ring? Would look nice on a napkin. Origin India, Philippines, anywhere else in South-Southeast Asia, take your pick.

 

That's what I thought. Napkin ring. Construction is resin, shell and whatever else they could find that looked good over a wood base.