Vintage Turquoise Sterling Filigree Ring Signed RJ Size 6

Beautiful vintage sterling ring featuring pretty filigree sides and a green and brown/black mottled stone, signed RJ. I believe it's turquoise but I'm not positive. Marked inside the band RJ, 6, and 925. It's an approximate size 6, and it measures 5/8" wide in the center and weighs five grams on my scale. Great vintage condition with just some light tarnish.