❤️Carved Chinese “jade” heart pendant necklace

Carved Chinese ”jade” heart pendant necklace Looks like Chinese jade with that opaque pale celadon green colour but I believe this is another stone. It’s hard and cold. New. Vintage c. 1970s-1980s. Gold tone bail. 18” Gold plate curb chain necklace (almost 1 mm thick). No visible hallmarks. The chain is very shiny but a little dark. C. 20x20 mm heart. Probably hand carved and / or polished. From China. Note: there is a dark spot on the heart (second picture). I can feel something when I run my nail over the spot. I think it’s a small pit