Vintage Large Sterling Jade & Marcasite Ring - Size 9

Ring has no 925 or STERLING stamp, but it appears to be silver and is NOT magnetic. I also put it on an ice cube and the ring melted the area that it was touching. Backed by green stone. The green has irregularities so I think it is truly jade. Not sure is it could be jadeite or nephrite...? The last 3 photos are taken with the stone backlit with a small flashlight. The stone is slighly translucent. Silver studded with marcasite. Size 9. Please refer to photos for condition.