Late 19th/early 20th century Ostby & Barton pieces are rare and collectible examples of jewelry because the co-owner of the company, Ostby, was a first class passenger on the Titanic & was one of the 1,500 passengers who perished during the tragic iceberg collision, his daughter surviving to carry on the business. Hallmarked "O[10k]B", no monogram. Ring size 9, Weighs 6.2 grams. U.S. SHIPPING $15 + INSURANCE. Source: http://www.maejeanvintage.com/blog/2014/3/20/titantic-jewelry and http://www.maejeanvintage.com/blog/2016/1/25/history-of-ostby-barton-jewelry-co-the-significance-of-the-historical-titantic-collision U.S. SHIPPING $15 + INSURANCE