Featured 3 brooches, 2 questions

I'm not going out to any sales these days, so I'm picking through accumulated "stuff" here at home.
First question - do you think the yellow, green, orange cabochon is glass or something else?
Second question - what are the attached loops on the goldstone mosaic pin used for? If just on the bottom, I would think for a dangle of some kind, but there is also one on the top. That one could be for a jump ring to wear as a pendant, but then that loop would show when worn as a pin, so I don't think it is for that. I also don't know if the attached pearl tassel could be original. I believe the pearls are real.

 

The little ring is for a safety chain. It's very good mosaic, are you sure it isn't gold? That other one looks like a layered pudding: glass I think.

 

So it is OBB, thank you very much! It does test gold. I usually test everything, but didn't test this because the pin stem was kind of darkened and just didn't look like gold to me. Well, the pin stem isn't gold, but the frame is. The pin stem does not look replaced, but is not gold.
So, that tassel does not belong there, right?
I don't understand how the safety chain would work, off to go search.

 

Saw quite a few with safety chains, but they didn't have the little loops so prominently visible. The loops seem to detract from the pin to me. Perhaps there was a fancy chain that was part of the design of the pin?

 

The tassel is fine. The safety chain would have been attached to that top ring - a fine chain with a safety pin? The only other option is that it had a faancy bale matching the one on the tassel, but I think safety chain is more likely. 1920s ish, and I bet it's 18 carat. The pins were often steel.

 

If the pearls were original to the pin the top ring would have connected to a necklace chain.
I'm not so sure it was a safety chain.

Late 1800s Goldstone Micromosaic
Asking:
https://www.ebay.com/sch/i.html?_fr....TRS1&_nkw=goldstone+micromosaic+pin&_sacat=0

Completeds
https://www.ebay.com/sch/i.html?_fr...n&_sacat=0&LH_TitleDesc=0&rt=nc&LH_Complete=1

 

The glass one appears to be silver plated

 

Seems the links aren't working.
Completeds

 

That back is later than Victorian, tho'. 1920s ish.