New vintage 925 jade heart pendant necklace

New vintage 925 jade heart pendant necklace Simple classic minimalist. Open heart with reverse curves on either side (convex + concave). 15x15 mm + 2x5 mm bail Simple oval jade cabochon. 4x7 mm Very fine silver tone curb chain. 16”, 1 mm New vintage c. 1970s. Genuine silver pendant with Hallmark: “925” on bail. No visible hallmark on chain, may be silver or silver plate. Guessing made in Mexico? Note: pendant and spring ring were black. I polished it a little with toothpaste and warm water.