Heirloom stolen- my grandmothers ring! (Santiago de Chile)

hi everyone,
I need advice, I stayed with a Chilean family, a friend of a friends family and the day I left I had left behind several items , one being my grandmothers ruby and diamond ring. I rang that same day to talk to the son- who speaks English to let his parents know, he said yes my mum has it all! I went back to collect it and all but one thing - not of any use to them- had disappeared, the ring being the only thing I want back I need to know of any pawn shops in las condes or near Los dominicos to try and find it? Any recommendations welcome, thanks!