Vintage Poodle Brooch Sterling Pltd Rhinestones

I've done so much research trying to make out the stamp on the back. I found one which is identical with the mark "Sterling", however it is next to impossible to make out without a jewelers loup. Even with that it's hard. It's gold plated over Sterling, little turquoise glass ball collar, measures 1 1/2 by 1 inch. No chips nor wear.