Microscopic examination of the structural joints of ancient metal artifacts reveals the use of joining methods that cannot be understood in terms of metalworking practices of the 19th and 20th centuries. A 9th and a 12th century manuscript were studied to determine the feasibility of 31 antique soldering formulas for gold, silver, bronze, brass, and tin. Reproduction of ancient recipes includes purpose of formula, ingredients and quantity and directions for use. The formulas were categorized into five classifications according to the author's interpretation of the text: copper acetate and copper oxide formulas; flux formulas; mercury formulas; silver and gold alloy solders and copper alloy solders; and tin and lead solders. Such a study increases current understanding and appreciation of the technical achievements of the metalsmiths of antiquity. See also AATA 8-1502, and 12-503. -- AATA