Long Antique Silver, Gold, Turquoise and Diamond Snake Necklace. Photo: Courtesy Doyle New York

Composed of graduated articulated silver links continuously set with three rows of collet-set round cabochon turquoise approximately 8.0 to 2.4 mm., backed by engraved gold scales, joined by a large silver snake head encrusted with 112 old-mine cut diamonds approximately 8.65 cts., accented by small round cabochon turquoise eyes, the reverse decorated with engraved gold scales, approximately 136.4 dwt. Length 37 1/2 inches.  Estimate $20,000-30,000

Doyle New York. Important Estate Jewelry - Wednesday, September 21, 2011 at 10am. www.doylenewyork.com