Vintage, 18K White Gold Engagement & Wedding Band

Vintage, 18K White Gold & Wedding Band. Diamond appears to be roughly a quarter karat. This was my Grandmothers wedding band & engagement ring. I’m thinking year would be approximately early 1900s. I’m thinking the size is approximately a size 4 and the band is a 5. I’ve stored this ring for over 45 years after it was passed down to me. Additional information and additional pictures welcomed. Remember any items over $500 will go to Poshmark for authenticity. ALL REASONABLE OFFERS WELCOMED. I ship same day as long as the post office is open.