vintage Stacked diamond ring w/certificate of authenticity

Vintage Silver coloured diamond ring. Belonged to my grandmother, has been stored away for decades. Comes with a certificate of authenticity for the diamonds. Not sure if real silver. Not sure of size. Around 7 or 8 maybe? I am also open to trades for things like senior cat food, wet cat food, paper towel, toilet paper, dog chews, handsoap, feminine hygiene products, sandwich meats, veggies, fruits, salads, cat litter, milk, any food besides mango due to allergies, fat free/low fat dog treats,etc. Basic necessities or gift cards to places for basic necessities. Located between Steeles ave. and Finch ave. on Yonge St. (No access to a vehicle) but willing to meet along the TTC subway system. Please feel free to check my other posts. Open to price negotiation as every dollar helps right now to feed my pets, myself, and buy needed medication while I recover from illness.