This is a wonderful estate piece. It is crafted from solid 18k yellow gold. The green stone i have not had tested. It looks like green chalcedony but again i have not had the green tested. The gold is hallmarked 750 on the bail for 75% pure gold or solid 18k (see last pic). This is a good sized pendant measuring 1.5" without the bail or 1.75" with the bail. This is in good condition and weighs in at 5 grams. good luck