Vintage Navajo Southwestern 925 Sterling Silver Concho Necklace – Antique & Rare. .925 sterling silver is acid and sigma tested – 100% authentic. Necklace measures 30.5″ long. This piece is likely from the pre-1900s – given it is real silver and not stamped. A truly rare, old, and remarkable piece to add to any wardrobe! This is 64.9G of silver alone.