Help with dating a bakelite necklace

Thanks very much, Laura. I am finding it really interesting researching this necklace! The links and discussion here have pointed me to lots of useful web resources. Whether or not the necklace is by Auguste Bonaz, I'm very pleased I have discovered his jewellery. The pictures online are stunning!

 

You definitely don't want it to be abrasive, Ruth. That's one of my issues with Simichrome. As well as the fact, that it can give (in my personal experience) false/positives.