Skip to main content.

Smithsonian National Museum of Natural History

Logan Sapphire

Logan Sapphire. A cushion-mixed-cut, medium-blue sapphire pendant. Described as
Photo by Chip Clark and digitally enhanced by SquareMoose. Click to zoom.
Catalog Number NMNH G3703-00
Locality Sri Lanka
Weight 423 ct

Gift of Mrs. John A. Logan in 1960.

The magnificent 423-carat Logan Sapphire was cut from a crystal mined in Sri Lanka and is one of the world’s largest faceted blue sapphires. It is the heaviest mounted gem in the National Gem Collection, and in its silver and gold brooch setting is framed by twenty round brilliant cut diamonds, totaling approximately 16 carats. Historically the finest sapphire gems came from Sri Lanka, Burma, and the Kashmir region of India. Sapphires from Sri Lanka are typically light to medium blue in color and are commonly referred to as “Ceylon Sapphires.” As seen here, the Logan Sapphire is a mixed cushion cut and is blue in color with very slight violet overtones. Under longwave ultraviolet radiation the stone fluoresces a moderate reddish-orange. A Gemological Institute of America (GIA) report dated June 1997 states that the Logan Sapphire’s color is natural with no evidence of heat treatment detected. The Logan Sapphire was a gift to the Smithsonian from Rebecca Pollard Guggenheim in December 1960. She had received it as a Christmas/anniversary gift in late 1952 or early 1953 from her then husband, Col. M. Robert Guggenheim. She retained possession of the piece until April 1971. By that time, she was married to John A. Logan, hence the Logan name. Before Guggenheim purchased the gem, it belonged to Sir Ellice Victor Sassoon, third Baronet of Bombay. Supposedly the Sassoon family acquired the gem from a maharajah in India.



Landscape mode is not currently supported for this website