18K Jade Disc about 40 years or so old

Good Evening,

This was passed down to me by a family member. It is at least 40 years old if not more. I'm not sure of the weight, but it is about 1 inch by 1 inch. It is definitely Jade and also is Marked 18K. It is a double-sided pendant with 2 different designs on either side. If anyone knows anything about this item please let me know. I have been searching endlessly for weeks on the internet looking for a piece like this. Have seen some like it, but none quite this unique. Thank you in advance for your help and time. 

Regards