Featured ID Material in Sterling Bracelet?

I've had this 7.5" long bracelet for awhile, and don't recall where I got it. It was so black I only recently saw the Italian hallmarks on it, then gave it a light polishing.
I am wondering what the translucent amber-colored "curved bar" material is. It has a crinkle finish like something organic that has been exposed to heat, but that is just a guess. Might it actually be amber, or...?
According to silvercollection.it, the mark [81 AR] belonged to Castellucci Udisse & Carniani Patrizio s.d.f. of Arezzo Province.
I haven't done anything with it in the years I've had it, because it just struck me as an interesting design, simple though it is. Will probably sell it eventually, if I can learn something about it.
Thanx in advance to you Knowledgeable Ones who always step up and share!

 

Do you recall whether the amber colored section looked like this when you got it?

 

Yes, it did.

 

I'm teetering between horn and acrylic.

 

Can't help, but have to admire your photographs. Super!

 

I'd suspect acrylic. How does it look under UV?

 

It has a faint green glow under my very weak UV penlight.

 

Thank you - I've been working on that for the past 23 years of selling on eBay!
My latest lighting system is the best, so far - three 4' LED lights (total of 4 rows, 20,000 lumens, I think) hung over and in front of my old 3' white EZ-Cube (top cut out for better light) within a cheap wooden framework I slapped together. Best thing about the LED lights, WAY LESS heat AND wattage than the halogen lamps I had been using!
I'm still using an ancient Sony DSC-H1 camera. I hope/expect to come across a good deal on a decent DSLR camera one of these days, but meanwhile, I've learned to do well with minimal equipment and a lot of practice!
Although not great by today's standards, this Sony model has sufficient features, including ability to focus down to an inch or so, and adjustable white balance.

 

Doesn't the green glow under UV suggest amber?

 

The amber glow is very distinctive, it's a bluish veil effect. That cracking suggests acrylic which has aged.

 

JMHO. Arezzo town is a hotspot for jewelry of all kinds and many small manifatture work exclusively for nearby Florence alta moda businesses.
this looks 60s to 70s IMO.

 

I'd say late 70's well into the 80's......based only on my travels to Italy ..thru that period...

 

could be. I was not so keen on visiting jewellers.

 

Just for kicks, here's a photo taken with my little UV penlight: