Now considered a birth stone for the month of December, turquoise was highly prized in the Middle Ages for its talismanic properties, thought to give contentment to the wearer. It was also believed to protect against illness, poisoning, or accidents while riding horseback. Varying from blue to green in color, high-quality blue stones were the most highly valued in lapidary books written in Arabic and Latin. The color of turquoise was thought to change when it was near a poisonous substance, or if its wearer fell ill the color of turquoise would change out of sympathy. Shakespeare places a turquoise ring in the possession of Shylock in The Merchant of Venice that represented his youth; when it was stolen by his daughter and traded for a pet monkey Shylock says that he “would not have given it [away] for a wilderness of monkeys.” In Western Europe turquoise was frequently set in petite flower-shaped bezels and in cluster designs. A lozenge-shaped blue turquoise stone is set in yellow gold and flanked with cut rock crystal in this Baroque cluster ring, creating an opaque, translucent and reflective bouquet. A tall tart-mold ring and a tiny “pinkie” ring are examples of more widely-available designs.