Featured Peruvian bracelet/cuff - silver or plate?

This is a mid-1900's bracelet or cuff made by Industria Peruana of Peru. It is marked 900, but it also has an SP which could be the artist initials, but I suspect it means it's silver plate. One of the sections has some odd bubbling looking thing going on, which also makes me think plate. But would silver plate also be marked 900? What's the point of that? Although I couldn't find any just like this, there are similar Peruana bracelets, and the sellers always just say .900 silver. It's pretty heavy (the little figures are very three dimensional though maybe hollowed in back), so it would have a fair value just from the melt value of silver alone if it were actually .900. What do you think?

 

The "bubbles"are from wax pattern casting,they didn't apply a debubblizer to the pattern before pouring the investment.

 

It's .900 silver, not plate. 90% silver instead of sterling. SP was probably the maker.

 

Here's another Peru bracelet with the same SP mark.

https://www.ebay.com/itm/1161528586...3TEEFZHs2MhalXr1YL0qIrYA==|tkp:Bk9SR7LR2e7fYw

Debora

 

Definitely silver. I’ve got some of their work.

 

It has some Modernist influence, so probably 1960s.
Peru is a silver country. I have yet to see Peruvian silverplate jewellery. When I was there in the early 70s silver jewellery was cheap, no need for silverplate jewellery.